WO2014199279A1

WO2014199279A1 - Building insulation

Info

Publication number: WO2014199279A1
Application number: PCT/IB2014/062034
Authority: WO
Inventors: Vasily A. Topolkaraev; Ryan J. Mceneany; Neil T. Scholl; III Charles W. COLMAN; Steven R. Stopper; Mark M. Mleziva
Original assignee: Kimberly-Clark Worldwide, Inc.
Priority date: 2013-06-12
Filing date: 2014-06-06
Publication date: 2014-12-18
Also published as: MX2015017042A; US20160130799A1; CN105264152B; CN105264152A; AU2014279706B2; KR20160019929A; KR102202850B1; RU2621112C1; EP3008260A4; AU2014279706A1; JP2016530409A; BR112015030934B1; EP3008260A1; BR112015030934A2

Abstract

A building structure containing a building envelope that defines an interior is provided. The building structure includes building insulation positioned adjacent to a surface of the building envelope, the interior, or a combination thereof. The building insulation may include a porous polymeric material that is formed from a thermoplastic composition containing a continuous phase that includes a matrix polymer. A microinclusion additive and nanoinclusion additive may also be dispersed within the continuous phase in the form of discrete domains, wherein a porous network is defined in the material that includes a plurality of nanopores having an average cross-sectional dimension of about 800 nanometers or less.

Description

BUILDING INSULATION

Related Applications

The present application claims priority to U.S. provisional application serial nos, 61/834,038, filed on June 12, 2013, which is incorporated herein in its entirety by reference thereto.

Insulation is employed in building structures for a wide variety of purposes, such as for protection against heat transfer, moisture, noise, vibration, etc. One type of building insulation, for instance, is a water-impermeable housewrap used in the construction of wall and roof assemblies, In addition to preventing the entrance of water into the building, such housewraps are also typically breathable to the extent they are permeable to gases and can allow water vapor to escape from the insulation rather than becoming trapped on a building surface.

Unfortunately, one of the common problems associated with many conventional types of building insulation, such as housewraps, is that they are not generally multi-functional. For example, a conventional breathable housewrap material is a flash spun polyolefin material available from DuPont under the designation

Tyvek®. While providing good water barrier properties, Tyvek© housewraps do not generally provide a good thermal barrier. To this end, polymeric foams are often employed for the purpose of thermal insulation. However, such materials do not necessarily function well as a breathable wafer barrier. Furthermore, the gaseous blowing agents used to form the foams can leach out of the insulation over time, causing an environmental concern.

As such, a need currently exists for an improved insulation material for use in building structures.

Summary of the Invention

In accordance with one embodiment of the present invention, building insulation for use in a residential or commercial building structure is disclosed. The building insulation includes a porous polymeric material that is formed from a thermoplastic composition containing a continuous phase that includes a matrix polymer. The polymeric material exhibits a water vapor transmission rate of about 300 g/m²-24 hours or more, thermal conductivity of about 0.40 watts per meter- kelvin or less, and/or hydrohead value of about 50 centimeters or more. In accordance with one embodiment of the present invention, building insulation for use in a residential or commercial building structure is disclosed. The building insulation includes a porous polymeric material that is formed from a thermoplastic composition containing a continuous phase that includes a matrix polymer. A microindusion additive and nanoinciusion additive are dispersed within the continuous phase in the form of discrete domains, wherein a porous network is defined in the material that includes a plurality of nanopores having an average cross-sectional dimension of about 800 nanometers or less.

In accordance with yet another embodiment, a building structure is disclosed that comprises a building envelope that defines an interior. The building structure further comprises building insulation, such as described herein, which is positioned adjacent to a surface of the building envelope, the interior, or a combination thereof. For example, in one embodiment, the building insulation may be positioned adjacent to a surface of the building envelope, such as adjacent to an exterior wall, roof, or a combination thereof. If desired, the building insulation may also be positioned adjacent to an exterior covering (e.g., siding). The building insulation may also be positioned adjacent to a surface of the interior, such as adjacent to an interior wall, floor, ceiling, door, or a combination thereof.

Other features and aspects of the present invention are discussed in greater detail below.

A full and enabling disclosure of the present invention, including the best mode thereof, directed to one of ordinary skill in the art, is set forth more

particularly in the remainder of the specification, which makes reference to the appended figures in which:

Fig. 1 shows a partial representative view of a building foundation wall fabricated with a building panel that may be formed in accordance with the invention;

Fig. 2 is an average cross-sectional dimension of the building pane! of Fig. 1 along a line 2-2;

Fig. 3 is a perspective view of one embodiment of a building structure in which the building insulation of the present invention is positioned adjacent to an exterior wail; Fig. 4 is a perspective view of one embodiment of a building structure in which the building insulation of the present invention is positioned adjacent to an interior wall;

Figs. 5-6 are SEM rnicrophotographs of the unstretched film of Example 7 (film was cut parallel to machine direction orientation);

Figs. 7-8 are SEM rnicrophotographs of the stretched film of Example 7 (film was cut parallel to machine direction orientation);

Figs. 9-10 are SEM rnicrophotographs of the unstretched film of Example 8, where the film was cut perpendicular to the machine direction in Fig. 9 and parallel to the machine direction in Fig. 10;

Figs. 11-12 are SEM rnicrophotographs of the stretched film of Example 8 (film was cut parallel to machine direction orientation);

Fig. 13 is an SEM photomicrograph (1 ,00ΌΧ) of the fiber of Example 9 (polypropylene, polylactic acid, and polyepoxide) after freeze fracturing in liquid nitrogen;

Fig. 14 is an SEM photomicrograph (5,00QX) of the fiber of Example 9 (polypropylene, polylactic acid, and polyepoxide) after freeze fracturing in liquid nitrogen: and

Fig. 15 is an SEM photomicrograph (10.000X) of the fiber surface of Example 9 (polypropylene, polylactic acid, and polyepoxide).

Repeat use of references characters in the present specification and drawings is intended to represent same or analogous features or elements of the invention.

Detailed Description of Representative Embodiments Reference now will be made in detail to various embodiments of the invention, one or more examples of which are set forth below. Each example is provided by way of explanation of the invention, not limitation of the invention. In fact, if will be apparent to those skilled in the art that various modifications and variations may be made in the present invention without departing from the scope or spirit of the invention. For instance, features illustrated or described as part of one embodiment, may be used on another embodiment to yield a still further embodiment. Thus, it is intended that the present invention covers such

modifications and variations as come within the scope of the appended claims and their equivalents.

Generally speaking, the present invention is directed to building insulation that contains a porous polymeric material (e.g., film, fibrous material, etc.). As used herein, the term "building insulation" refers broadly to any object in a building used as insulation for any purpose, such as for thermal insulation, acoustic insulation, impact insulation (e.g., for vibrations), fire insulation, moisture insulation, etc., as well as combinations thereof. The building insulation may be positioned in a residential or commercial building structure so that it is adjacent to a surface of the building envelope, which is the physical separator between the interior and the exterior environments of a building and may include, for instance, the foundation, roof, exterior walls, exterior doors, windows, skylights, etc. The building insulation may also be positioned adjacent to an interior surface of the building, such as an interior wall, interior door, flooring, ceilings, etc.

Regardless of the particular location in which the building insulation is employed, the porous polymeric material of the present invention may serve multiple insulative functions within the building, and in some cases, even eliminating the need for certain types of conventional insulation. For instance, the polymeric material is porous and defines a porous network which, for instance, may constitute from about 15% to about 80% per cm³, in some embodiments from about 20% to about 70%, and in some embodiments, from about 30% to about 80% per cubic centimeter of the material. The presence of such a high pore volume can allow the polymeric material to be generally permeable to water vapors, thereby allowing such vapors to escape from a building surface during use and limit the likelihood of water damage over time. The permeability of the material to water vapor may characterized by its relatively high water vapor transmission rate ("WVTR"), which is the rate at which water vapor permeates through a material as measured in units of grams per meter squared per 24 hours (g/m²/24 hrs). For example, the poiymeric material may exhibit a WVTR of about 300 g/m²~24 hours or more, in some embodiments about 500 g/m²~24 hours or more, in some embodiments about 1 ,000 g/m²~24 hours or more, and in some embodiments, from about 3,000 to about 15,000 g/m²-24 hours, such as determined in accordance with ASTM E96/96M-12, Procedure B or INDA Test Procedure IST-70.4 (01 ). In addition to allowing the passage of vapors, the relatively high pore volume of the material can also significantly lower the density of the material, which can allow the use of lighter, more flexible materials that stiii achieve good insulative properties. For example, the composition may have a relatively low density, such as about 1.2 grams per cubic centimeter ("g/cm ") or less, in some embodiments about 1.0 g/cm^J or less, in some embodiments from about 0.2 g/cm³ to about 0.8 g/cm³, and in some embodiments, from about 0.1 g/cm³ to about 0.5 g/cm³. Due to its low density, lighter materials may be formed that still achieve good thermal resistance.

Despite being highly porous and generally permeable to water vapor, the present inventors have nevertheless discovered that the porous network may be considered a "closed-cell" network such that a tortuous pathway is not defined between a substantial portion of the pores. Such a structure can help restrict the flow of fluids through the material and be generally impermeable to fluids (e.g., liquid water), thereby allowing the material to insulate a surface from water penetration, in this regard, the polymeric material may have a relatively high hydrohead value of about 50 centimeters ("cm") or more, in some embodiments about 100 cm or more, in some embodiments, about 150 cm or more, and in some embodiments, from about 200 cm to about 1000 cm, as determined in accordance with ATTCC 127-2008.

A substantial portion of pores in the polymeric material may also be of a "nano-scale" size ("nanopores"), such as those having an average cross-sectional dimension of about 800 nanometers or less, in some embodiments from about 1 to about 500 nanometers, in some embodiments from about 5 to about 450 nanometers, in some embodiments from about 5 to about 400 nanometers, and in some embodiments, from about 10 to about 100 nanometers. The term "cross- sectional dimension" generally refers to a characteristic dimension (e.g., width or diameter) of a pore, which is substantially orthogonal to its major axis (e.g., length) and also typically substantially orthogonal to the direction of the stress applied during drawing. Such nanopores may, for example, constitute about 15 vol.% or more, in some embodiments about 20 vol.% or more, in some embodiments from about 30 vol.% to 100 vol.%, and in some embodiments, from about 40 vol.% to about 90 vol.% of the total pore volume in the polymeric material. The presence of such a high degree of nanopores can substantially decrease thermal conductivity as fewer cei! molecules are available within each pore to collide and transfer heat. Thus, the polymeric material may also serve as thermal insulation to help limit the degree of heat transfer through the building structure.

To this end, the polymeric material may exhibit a relatively low thermal conductivity, such as about 0,40 watts per meter-kelvin ("W/m-K") or less, in some embodiments about 0.20 W/m-K or less, in some embodiments about 0,15 W/m-K or less, in some embodiments from about 0.01 to about 0.12 W/m-K, and in some embodiments, from about 0.02 to about 0.10 W/m-K. Notably, the material is capable of achieving such low thermal conductivity values at relatively low thicknesses, which can allow the material to possess a greater degree of flexibility and conformability, as well as reduce the space it occupies in a building. For this reason, the polymeric material may also exhibit a relatively low "thermal

admittance", which is equal to the thermal conductivity of the material divided by its thickness and is provided in units of watts per square meter-kelvins W/m²K"). For example, the material may exhibit a thermal admittance of about 1000 W/m²K or less, in some embodiments from about 10 to about 800 W/m²K, in some

embodiments from about 20 to about 500 W/m K, and in some embodiments, from about 40 to about 200 W/m²K. The actual thickness of the polymeric materiai may depend on its particular form, but typically ranges from about 5 micrometers to about 100 millimeters, in some embodiments from about 10 micrometers to about 50 millimeters, in some embodiments from about 200 micrometers to about 25 millimeters, and in some embodiments, from about 50 micrometers to about 5 millimeters.

Contrary to conventional techniques for forming building insulation materials, the present inventors have discovered that the porous material of the present invention can be formed without the use of gaseous blowing agents. This is due in part to the unique nature of the components of the material, as well as the matter in which the materiai is formed. More particularly, the porous materiai may be formed from a thermoplastic composition containing a continuous phase that includes a matrix polymer, microinclusion additive, and nanoinclusion additive. The additives may be selected so that they have a different elastic modulus than the matrix polymer. In this manner, the microinclusion and nanoinclusion additives can become dispersed within the continuous phase as discrete micro-scale and nano-scaie phase domains, respectively. The present inventors have discovered that the micro-sca!e and nano-scale phase domains are able to interact in a unique manner when subjected to a deformation and elongational strain (e.g., drawing) to create a network of pores, a substantial portion of which are of a nano-scale size. Namely, it is believed that elongational strain can initiate intensive localized shear zones and/or stress intensity zones (e.g., normal stresses) near the micro-scale discrete phase domains as a result of stress concentrations that arise from the incompatibility of the materials. These shear and/or stress intensity zones cause some initial debonding in the polymer matrix adjacent to the micro-scale domains. Notably, however, localized shear and/or stress intensity zones may also be created near the nano-scale discrete phase domains that overlap with the micro- scale zones. Such overlapping shear and/or stress intensity zones cause even further debonding to occur in the polymer matrix, thereby creating a substantial number of nanopores adjacent to the nano-scale domains and/or micro-scafe domains.

Various embodiments of the present invention will now be described in more detail.

i- Thermoplastic Composition

A. Matrix Polymer

As indicated above, the thermoplastic composition may contain a

continuous phase that contains one or more matrix polymers, which typically constitute from about 60 wt.% to about 99 wt.%, in some embodiments from about 75 wt.% to about 98 wt.%, and in some embodiments, from about 80 wt.% to about 95 wt.% of the thermoplastic composition. The nature of the matrix polymer(s) used to form the continuous phase is not critical and any suitable polymer may generally be employed, such as polyesters, polyolefins, styrenic polymers,

po!yamides, etc. In certain embodiments, for example, polyesters may be employed in the composition to form the polymer matrix. Any of a variety of polyesters may generally be employed, such as aliphatic polyesters, such as polycaproiactone, polyesteramides, polylactic acid (PLA) and its copolymers, poiyglycolic acid, polyalkylene carbonates (e.g. , polyethylene carbonate), poly-3- hydroxybutyrate (PHB), poiy-3-hydroxyvalerate (PHV), poiy-3-hydroxybutyrate-co- 4-hydroybutyrate, poly-3-hydroxybutyrate-co-3-hydroxyvaierate copolymers (PHBV), poly-S-hydroxybutyrate-co-S-hydroxyhexanoate, poly-3-hydroxybutyrate- co-3-hydroxyoctanoate, poly-3-hydroxybutyrate-co-3-hydroxydecanoate, poly-3~ hydroxybutyrate-co-3-hydroxyoctadecanoate, and succinate-based aliphatic polymers (e.g., poiybutyfene succinate, polybutyiene succinate adipate,

polyethylene succinate, etc.); aliphatic-aromatic copoiyesters (e.g., poiybutyfene adipate terephthaiate, polyethylene adipate terephthalate, polyethylene adipate isophthalate, poiybutyfene adipate isophthalate, etc.); aromatic polyesters (e.g., polyethylene terephthalate, poiybutyfene terephthafate, etc.); and so forth.

In certain cases, the thermoplastic composition may contain at least one polyester that is rigid in nature and thus has a reSatively high glass transition temperature. For example, the glass transition temperature ("T_g") may be about 0°C or more, in some embodiments from about 5°C to about 100°C, in some embodiments from about 30°C to about 80°C, and in some embodiments, from about 50°C to about 75°C. The polyester may also have a melting temperature of from about 140°C to about 30G°C, in some embodiments from about 150°C to about 250°C, and in some embodiments, from about 160°C to about 220°C. The mefting temperature may be determined using differential scanning calorimetry ("DSC") in accordance with ASTM D-3417. The glass transition temperature may be determined by dynamic mechanical analysis in accordance with ASTM E1640- 09.

One particularly suitable rigid polyester is po!ylactic acid, which may generally be derived from monomer units of any isomer of lactic acid, such as levorotory-Sactic acid ("L-lactic acid"), dextrorotatory-lactic acid ("D-lactic acid"), meso-Sactic acid, or mixtures thereof. Monomer units may also be formed from anhydrides of any isomer of iactic acid, including L-lactide, D-lactide, meso-Sactide, or mixtures thereof. Cyclic dimers of such iactic acids and/or lactides may also be employed. Any known polymerization method, such as polycondensation or ring- opening polymerization, may be used to polymerize lactic acid. A small amount of a chain-extending agent (e.g., a diisocyanate compound, an epoxy compound or an acid anhydride) may also be employed. The polylactic acid may be a

homopoiymer or a copolymer, such as one that contains monomer units derived from L-lactic acid and monomer units derived from D-lactic acid. Although not required, the rate of content of one of the monomer unit derived from L-lactic acid and the monomer unit derived from D-lactic acid is preferably about 85 moie% or more, in some embodiments about 90 mole% or more, and in some embodiments, about 95 moie% or more. Multiple polylactic acids, each having a different ratio between the monomer unit derived from L-lactic acid and the monomer unit derived from D-lactic acid, may be blended at an arbitrary percentage. Of course, polylactic acid may also be blended with other types of polymers (e.g., polyo!efins, polyesters, etc.).

In one particular embodiment, the polylactic acid has the following general structure:

One specific example of a suitable polylactic acid polymer that may be used in the present invention is commerciaily available from Biomer, Inc. of Kraiiling, Germany) under the name B!GMER™ L9000, Other suitable polylactic acid polymers are commercially available from Natureworks LLC of Minnetonka, Minnesota (NATUREWORKS®) or Mitsui Chemical (LACEA™). Still other suitable polylactic acids may be described in U.S. Patent Nos. 4,797,488; 5,470,944;

5,770,682; 5,821 ,327; 5,880,254; and 8,328,458.

The polylactic acid typically has a number average molecular weight ("M_n") ranging from about 40,000 to about 180,000 grams per mole, in some

embodiments from about 50,000 to about 180,000 grams per mole, and in some embodiments, from about 80,000 to about 120,000 grams per mole. Likewise, the polymer also typically has a weight average molecular weight ("M_w") ranging from about 80,000 to about 250,000 grams per mole, in some embodiments from about 100,000 to about 200,000 grams per mo!e, and in some embodiments, from about 110,000 to about 160,000 grams per mole. The ratio of the weight average molecular weight to the number average molecular weight ("M_w/M_n"), i.e., the "polydispersity index", is also relatively low. For example, the poiydispersity index typically ranges from about 1.0 to about 3.0, in some embodiments from about 1.1 to about 2.0, and in some embodiments, from about 1.2 to about 1.8. The weight and number average molecular weights may be determined by methods known to those skilled in the art.

The polylactic acid may also have an apparent viscosity of from about 50 to about 600 Pascal seconds (Pa-s), in some embodiments from about 100 to about 500 Pa-s, and in some embodiments, from about 200 to about 400 Pa s, as determined at a temperature of 190°C and a shear rate of 1000 sec^"'1. The meit flow rate of the polylactic acid (on a dry basis) may also range from about 0,1 to about 40 grams per 10 minutes, in some embodiments from about 0.5 to about 20 grams per 10 minutes, and in some embodiments, from about 5 to about 15 grams per 10 minutes, determined at a load of 2160 grams and at 90°C.

Some types of neat polyesters (e.g., polylactic acid) can absorb water from the ambient environment such that it has a moisture content of about 500 to 800 parts per million ("ppm"), or even greater, based on the dry weight of the starting polylactic acid. Moisture content may be determined in a variety of ways as is known in the art, such as in accordance with ASTM D 7 91-05, such as described below. Because the presence of water during melt processing can hydrolyticaily degrade the polyester and reduce its molecular weight, it is sometimes desired to dry the polyester prior to blending. In most embodiments, for example, it is desired that the polyester have a moisture content of about 300 parts per million ("ppm") or less, in some embodiments about 200 ppm or less, in some embodiments from about 1 to about 100 ppm prior to blending with the microinclusion and

nanoinclusion additives. Drying of the polyester may occur, for instance, at a temperature of from about 50°C to about 00°C, and in some embodiments, from about 70°C to about 80°C.

B · icroincius ion Add stive

As indicated above, in certain embodiments of the present invention, microinclusion and/or nanoinclusion additives may be dispersed within the continuous phase of the thermoplastic composition. As used herein, the term "microinclusion additive" generally refers to any amorphous, crystalline, or semi- crystalline material that is capable of being dispersed within the polymer matrix in the form of discrete domains of a micro-scale size. For example, prior to drawing, the domains may have an average cross-sectional dimension of from about 0.05 prn to about 30 pm, in some embodiments from about 0.1 pm to about 25 pm, in some embodiments from about 0.5 pm to about 20 pm, and in some embodiments from about 1 pm to about 10 pm. The term "cross-sectional dimension" generally refers to a characteristic dimension (e.g., width or diameter) of a domain, which is substantially orthogonal to its major axis (e.g., length) and also typically

substantially orthogonal to the direction of the stress applied during drawing.

White typically formed from the microinclusion additive, it should be also

understood that the micro-scale domains may also be formed from a combination of the microinclusion and nanoinciusion additives and/or other components of the composition.

The microinclusion additive is generally polymeric in nature and possesses a relatively high molecular weight to help improve the melt strength and stability of the thermoplastic composition. Typically, the microinclusion polymer may be generally immiscible with the matrix polymer. In this manner, the additive can better become dispersed as discrete phase domains within a continuous phase of the matrix polymer. The discrete domains are capable of absorbing energy that arises from an external force, which increases the overall toughness and strength of the resulting material The domains may have a variety of different shapes, such as elliptical, spherical, cylindrical, plate-like, tubular, etc. In one embodiment, for example, the domains have a substantially elliptical shape. The physical dimension of an individual domain is typically small enough to minimize the propagation of cracks through the polymeric material upon the application of an external stress, but large enough to initiate microscopic plastic deformation and allow for shear and/or stress intensity zones at and around particle inclusions.

While the polymers may be Immiscible, the microinclusion additive may nevertheless be selected to have a solubility parameter that is relatively similar to that of the matrix polymer. This can improve the interfacial compatibility and physical interaction of the boundaries of the discrete and continuous phases, and thus reduces the likelihood that the composition will fracture. In this regard, the ratio of the solubility parameter for the matrix polymer to that of the additive is typically from about 0.5 to about 1.5, and in some embodiments, from about 0.8 to about 1.2. For example, the microinclusion additive may have a solubility parameter of from about 15 to about 30 Mjouies ^/2/m^{3 2}, and in some

embodiments, from about 18 to about 22 M Joules ^{1 2}/m³'², while polylactic acid may have a solubility parameter of about 20.5 MJouies ²/m³'^'2. The term "solubility parameter as used herein refers to the "Hiidebrand Solubility Parameter", which is the square root of the cohesive energy density and calculated according to the following equation:

where:

Δ Hv ~ heat of vaporization

R = idea! Gas constant

T = Temperature

Vm = Molecular Volume

The Hiidebrand solubility parameters for many polymers are also available from the Solubility Handbook of Plastics, by Wyeych (2004), which is incorporated herein by reference.

The microinclusion additive may also have a certain melt flow rate (or viscosity) to ensure that the discrete domains and resulting pores can be adequately maintained. For example, if the melt flow rate of the additive is too high, it tends to flow and disperse uncontrollably through the continuous phase. This results in lamellar, plate-like domains or co-continuous phase structures that are difficult to maintain and also likely to prematurely fracture. Conversely, if the melt flow rate of the additive is too low, it tends to clump together and form very large elliptical domains, which are difficult to disperse during blending. This may cause uneven distribution of the additive through the entirety of the continuous phase. In this regard, the present inventors have discovered that the ratio of the melt flow rate of the microinclusion additive to the melt flow rate of the matrix polymer is typically from about 0.2 to about 8, in some embodiments from about 0.5 to about 6, and in some embodiments, from about 1 to about 5. The

microinclusion additive may, for example, have a melt flow rate of from about 0.1 to about 250 grams per 10 minutes, in some embodiments from about 0.5 to about 200 grams per 10 minutes, and in some embodiments, from about 5 to about 150 grams per 10 minutes, determined at a load of 2160 grams and at 190°C,

In addition to the properties noted above, the mechanical characteristics of the microinclusion additive may also be selected to achieve the desired increase in toughness. For example, when a blend of the matrix polymer and microinclusion additive is applied with an external force, stress concentrations (e.g., including normal or shear stresses) and shear and/or plastic yielding zones may be initiated at and around the discrete phase domains as a result of stress concentrations that arise from a difference in the elastic modulus of the additive and matrix polymer. Larger stress concentrations promote more intensive localized plastic flow at the domains, which allows them to become significantly elongated when stresses are imparted. These elongated domains can allow the composition to exhibit a more pliable and softer behavior than the matrix polymer, such as when it is a rigid polyester resin. To enhance the stress concentrations, the microinclusion additive may be selected to have a relatively low Young's modulus of elasticity in comparison to the matrix polymer. For example, the ratio of the modulus of elasticity of the matrix polymer to that of the additive is typically from about 1 to about 250, in some embodiments from about 2 to about 100, and in some embodiments, from about 2 to about 50. The modulus of elasticity of the microinclusion additive may, for instance, range from about 2 to about 1000 Megapascals (MPa), in some embodiments from about 5 to about 500 MPa, and in some embodiments, from about 10 to about 200 MPa. To the contrary, the modulus of elasticity of polylactic acid, for example, is typically from about 800 MPa to about 3000 MPa.

While a wide variety of microinclusion additives may be employed that have the properties identified above, particularly suitable examples of such additives may include synthetic polymers, such as polyolefins (e.g., polyethylene, polypropylene, polybutylene, etc.); styrenic copolymers {e.g., styrene-butadiene- styrene, styrene-isoprene-styrene, styrene-ethylene-propylene-sfyrene, styrene- ethylene-butadiene-sfyrene, etc.); polytetrafluoroethylenes; polyesters (e.g., recycled polyester, polyethylene terephthaiate, etc.); polyvinyl acetates (e.g., poly(ethylene viny! acetate), polyvinyl chloride acetate, etc.); polyvinyl alcohols (e.g., polyvinyl alcohol, poly(ethylene vinyl alcohol), etc.); polyvinyl butyrals; acrylic resins (e.g.. polyacrylate, poiymethylacrylate, polymethylmethacrylate, etc.);

polyamides (e.g., nylon); polyvinyl chlorides; polyvinylidene chlorides;

polystyrenes; polyurethanes; etc. Suitable polyolefins may, for instance, include ethylene polymers (e.g., low density polyethylene ("LDPE"), high density polyethylene ("HDPE"), linear low density polyethylene ("LLDPE"), etc.), propylene homopoiymers (e.g., syndiotactic, atactic, isotactic, etc.), propylene copolymers, and so forth.

In one particular embodiment, the polymer is a propylene polymer, such as homopoiypropylene or a copolymer of propylene. The propylene polymer may, for instance, be formed from a substantially isotactic polypropylene homopolymer or a copolymer containing equal to or less than about 10 wt.% of other monomer, i.e., at least about 90% by weight propylene. Such homopoiymers may have a melting point of from about 180°C to about 170°C.

In still another embodiment, the polyolefin may be a copolymer of ethylene or propylene with another a-oiefin, such as a C3-C20 a-olefin or C3-C12 a-olefin. Specific examples of suitable a-olefins include 1-butene; 3-methyl~1~butene; 3,3- dimethyl-1-butene; 1-pentene; 1-pentene with one or more methyl, ethyl or propyl substituents; 1-hexene with one or more methyl, ethyl or propyl substituents; 1- heptene with one or more methyl, ethyl or propyl substituents; 1-octene with one or more methyl, ethyl or propyl substituents; -nonene with one or more methyl, ethyl or propyl substituents; ethyl, methyl or dimethyl-substituted 1-decene; 1-dodecene; and styrene. Particularly desired α-olefin comonomers are 1~butene, 1-hexene and 1-octene. The ethylene or propylene content of such copolymers may be from about 60 mole% to about 99 mo!e%, in some embodiments from about 80 mole% to about 98.5 mole%, and in some embodiments, from about 87 moie% to about 97.5 mole%. The α-olefin content may likewise range from about 1 mole% to about 40 moie%, in some embodiments from about 1.5 mole% to about 15 mo!e%, and in some embodiments, from about 2.5 mole% to about 13 mole%.

Exemplary olefin copolymers for use in the present invention include ethylene-based copolymers available under the designation EXACT™ from

ExxonMobil Chemical Company of Houston, Texas. Other suitable ethylene copolymers are available under the designation ENGAGE™, AFFINITY™,

DOWLEX™ (LLDPE) and ATTANE™ (ULDPE) from Dow Chemical Company of Midland, Michigan. Other suitable ethylene polymers are described in U.S. Patent Nos. 4,937,299 to Ewen et at■ 5,218,071 to Tsutsui et at; 5,272,236 to Las, et al; and 5,278,272 to Lai, et al. Suitable propylene copolymers are also commercially available under the designations VISTAMAXX™ from ExxonMobil Chemical Co. of Houston, Texas: FINA™ (e.g., 8573) from Atofina Chemicals of Feluy, Belgium; TAFMER™ available from Mitsui Petrochemical industries; and VERSIFY™ available from Dow Chemicai Co. of Midland, Michigan. Suitable polypropylene hornopolymers may likewise include Exxon Mobil 3155 polypropylene, Exxon Mobil Achieve™ resins, and Total M3661 PP resin. Other examples of suitable propylene polymers are described in U.S. Patent Nos. 6,500.563 to Datta, et al.; 5,539,058 to Yang, et al.; and 5,598.052 to Resconi, et al.

Any of a variety of known techniques may generally be employed to form the olefin copolymers. For instance, olefin polymers may be formed using a free radical or a coordination catalyst (e.g., Ziegler-Natta). Preferably, the olefin polymer is formed from a single-site coordination catalyst, such as a metallocene catalyst. Such a catalyst system produces ethylene copolymers in which the comonomer is randomly distributed within a molecular chain and uniformly distributed across the different molecular weight fractions, Metaliocene-catalyzed polyolefins are described, for instance, in U.S. Patent Nos. 5,571 ,619 to McAlpin et aL; 5,322,728 to Davis et al.: 5,472,775 to Qbiieski et al.: 5,272,236 to Lai et al.: and 6,090,325 to Wheal et al. Examples of metallocene catalysts include bis(n- butylcyclopentadienyi)titanium dichloride, bis(n-butyicyclopeniadienyl)zirconium dichloride, bis(cyciopentadienyl)scandium chloride, b!s(indenyl)zirconium

dichloride, bis{methylcyclopentadienyl)titanium dichloride,

bis(methylcyclopentadienyl)zirconium dichloride, cobaltocene,

cyclopentadienyltitanium trichloride, ferrocene, hafnocene dichloride,

isopropyl(cycIopentadienyi,-1 -flourenyl)zirconium dichloride, moiybdocene dichloride, nickelocene, niobocene dichloride, ruthenocene, titanocene dichloride, zirconocene chloride hydride, zirconocene dichloride, and so forth. Polymers made using metallocene catalysts typically have a narrow molecular weight range , For instance, metaliocene-catalyzed polymers may have polydispersity numbers (M_w/M_n) of below 4, controlled short chain branching distribution, and controlled isotacticity.

Regardless of the materials employed, the relative percentage of the microinclusion additive in the thermoplastic composition is selected to achieve the desired properties without significantly impacting the base properties of the composition. For example, the microinclusion additive is typically employed in an amount of from about 1 wt.% to about 30 wt.%, in some embodiments from about 2 wt.% to about 25 wt.%, and in some embodiments, from about 5 wt.% to about 20 wt.% of the thermoplastic composition, based on the weight of the continuous phase (matrix polymer(s)). The concentration of the microinclusion additive in the entire thermop!astic composition may likewise constitute from about 0.1 wt.% to about 30 wt.%, in some embodiments from about 0.5 wt.% to about 25 wt.%, and in some embodiments, from about 1 wt.% to about 20 wt.%.

C . Nanoinclusion Additive

As used herein, the term "nanoinclusion additive" generally refers to any amorphous, crystalline, or semi-crystalline material that is capable of being dispersed within the polymer matrix in the form of discrete domains of a nano- scale size. For example, prior to drawing, the domains may have an average cross-sectional dimension of from about 1 to about 500 nanometers, in some embodiments from about 2 to about 400 nanometers, and in some embodiments, from about 5 to about 300 nanometers. It should be also understood that the nano-scaie domains may also be formed from a combination of the microinclusion and nanoinclusion additives and/or other components of the composition. The nanoinclusion additive is typically employed in an amount of from about 0.05 wt.% to about 20 wt.%, in some embodiments from about 0.1 wt.% to about 10 wt.%, and in some embodiments, from about 0.5 wt.% to about 5 wt.% of the

thermoplastic composition, based on the weight of the continuous phase (matrix poiymer(s)). The concentration of the nanoinclusion additive in the entire thermoplastic composition may likewise be from about 0.01 wt.% to about 15 wt.%, in some embodiments from about 0.05 wt.% to about 10 wt.%, and in some embodiments, from about 0.3 wt.% to about 6 wt.% of the thermoplastic

composition.

The nanoinclusion additive may be polymeric in nature and possess a relatively high molecular weight to help improve the melt strength and stability of the thermoplastic composition. To enhance its ability to become dispersed into nano-scaie domains, the nanoinclusion additive may a!so be selected from materials that are generally compatible with the matrix polymer and the

microinclusion additive. This may be particularly useful when the matrix polymer or the microinclusion additive possesses a polar moiety, such as a polyester. One example such a nanoinclusion additive is a functionalized polyolefin. The polar component may, for example, be provided by one or more functional groups and the non-polar component may be provided by an olefin. The olefin component of the nanoinclusion additive may generally be formed from any linear or branched a- olefin monomer, oligomer, or polymer (including copolymers) derived from an olefin monomer, such as described above.

The functional group of the nanoinclusion additive may be any group, molecular segment and/or block that provides a polar component to the molecule and is not compatible with the matrix polymer. Examples of molecular segment and/or blocks not compatible with polyolefin may include acrylates, styrenics, polyesters, polyamides, etc. The functional group can have an ionic nature and comprise charged metal ions. Particularly suitable functional groups are maieic anhydride, maieic acid, fumaric acid, maieimide, maieic acid hydrazide, a reaction product of maieic anhydride and diamine, methylnadic anhydride, dichloromaleic anhydride, maieic acid amide, etc. Maieic anhydride modified polyolefins are particularly suitable for use in the present invention. Such modified polyolefins are typically formed by grafting maieic anhydride onto a polymeric backbone material. Such maleated polyolefins are available from E. I. du Pont de Nemours and Company under the designation Fusabond®, such as the P Series (chemically modified polypropylene), E Series (chemically modified polyethylene), C Series (chemically modified ethylene vinyl acetate), A Series (chemically modified ethylene acrylate copolymers or terpolymers), or N Series (chemically modified ethylene-propylene, ethylene-propylene diene monomer ("EPDM") or ethylene- octene). Alternatively, maleated polyolefins are also available from Chemtura Corp. under the designation Polybond® and Eastman Chemical Company under the designation Eastman G series.

In certain embodiments, the nanoinclusion additive may also be reactive. One example of such a reactive nanoinclusion additive is a polyepoxide that contains, on average, at least two oxirane rings per molecule. Without intending to be limited by theory, it is believed that such polyepoxide molecules can induce reaction of the matrix polymer (e.g., polyester) under certain conditions, thereby improving its melt strength without significantly reducing glass transition

temperature. The reaction may involve chain extension, side chain branching, grafting, copolymer formation, etc. Chain extension, for instance, may occur through a variety of different reaction pathways. For instance, the modifier may enable a nucieophiiic ring-opening reaction via a carboxyi terminal group of a polyester (esterification) or via a hydroxy! group (etherification). Oxazo!ine side reactions may likewise occur to form esteramide moieties. Through such reactions, the moiecuiar weight of the matrix polymer may be increased to counteract the degradation often observed during melt processing. While it may be desirabie to induce a reaction with the matrix polymer as described above, the present inventors have discovered that too much of a reaction can !ead to crossiinking between polymer backbones. If such crossiinking is allowed to proceed to a significant extent, the resulting polymer blend can become brittle and difficult to process into a material with the desired strength and elongation properties.

In this regard, the present inventors have discovered that poiyepoxides having a relatively low epoxy functionality are particularly effective, which may be quantified by its "epoxy equivalent weight." The epoxy equivalent weight reflects the amount of resin that contains one molecule of an epoxy group, and it may be calculated by dividing the number average molecular weight of the modifier by the number of epoxy groups in the molecule. The polyepoxide of the present invention typically has a number average molecular weight from about 7,500 to about 250,000 grams per mole, in some embodiments from about 15,000 to about 150.000 grams per mole, and in some embodiments, from about 20,000 to

100,000 grams per mole, with a poiydispersity index typically ranging from 2.5 to 7. The polyepoxide may contain less than 50, in some embodiments from 5 to 45, and in some embodiments, from 15 to 40 epoxy groups. In turn, the epoxy equivalent weight may be less than about 15,000 grams per mole, in some embodiments from about 200 to about 10,000 grams per mole, and in some embodiments, from about 500 to about 7.000 grams per mole.

The polyepoxide may be a linear or branched, homopolymer or copolymer (e.g., random, graft, block, etc.) containing terminal epoxy groups, skeletal oxirane units, and/or pendent epoxy groups. The monomers employed to form such poiyepoxides may vary. In one particular embodiment, for example, the

polyepoxide contains at least one epoxy-functional (meth)acryiic monomeric component. As used herein, the term "(meth)acrylic" includes acrylic and methacry!ic monomers, as e!i as salts or esters thereof, such as acrylate and methacrylate monomers. For example, suitable epoxy-functionai (meth)acrylic monomers may include, but are not limited to, those containing 1 ,2-epoxy groups, such as giycidyi acrylate and giycidyl methacrylate. Other suitable epoxy- functional monomers include allyl giycidyl ether, giycidyi ethacryiate, and giycidyl itoconate.

The polyepoxide typically has a relatively high molecular weight, as indicated above, so that it may not only result in chain extension, but also help to achieve the desired blend morphology. The resulting melt flow rate of the polymer is thus typically within a range of from about 10 to about 200 grams per 10 minutes, in some embodiments from about 40 to about 150 grams per 10 minutes, and in some embodiments, from about 60 to about 120 grams per 10 minutes, determined at a load of 2160 grams and at a temperature of 190°C.

If desired, additional monomers may also be employed in the polyepoxide to help achieve the desired molecular weight. Such monomers may vary and include, for example, ester monomers, (meth)acrylic monomers, olefin monomers, amide monomers, etc. In one particular embodiment, for example, the

polyepoxide includes at least one linear or branched a-olefin monomer, such as those having from 2 to 20 carbon atoms and preferably from 2 to 8 carbon atoms. Specific examples include ethylene, propylene, 1-butene; 3-methyl-1-butene; 3,3- dimethyi-1-butene; 1-pentene; -pentene with one or more methyi, ethyl or propyl substituents; 1-hexene with one or more methyl, ethyl or propyl substituents; 1- heptene with one or more methyi, ethyl or propyl substituents; 1-octene with one or more methyl, ethyl or propyl substituents; 1-nonene with one or more methyl, ethyl or propyl substituents; ethyl, methyl or dimethyl-substituted 1-decene; 1-dodecene; and styrene. Particularly desired a-olefin comonomers are ethylene and

propylene.

Another suitable monomer may include a (meth)acrylic monomer that is not epoxy-functional. Examples of such (meth)acrylic monomers may include methyl acryiate, ethyl acrylate, n-propyS acrylate, i~propyS acrylate, n-butyl acrylate, s-butyj acrylate, i-butyl acrylate, t-butyl acrylate, n-amyl acrylate, i-amyl acrylate, isobornyi acrylate, n-hexy! acrylate, 2-ethylbutyl acrylate, 2-ethylhexyl acryiate, n-octyi acrylate, n-decyl acrylate, methylcyciohexyl acrylate, cyclopenty! acrylate, cyciohexyi acrylate, meihyi methacrylate, ethyl methacryiate, 2-hydroxyethyi rneihacryfate, n-propyi methacryiate. n~butyi methacrylate, i-propyl methacrylate, i- butyl methacrylate. n-amy! methacrylate, n-hexyl methacrylate, i-amyl

methacrylate, s-butyl-methacrylate, t-butyl methacryiate, 2-ethyibutyf methacrylate, methylcyclohexyl methacrylate, cinnamyl methacryiate, crotyi methacrylate, cyciohexyi methacryiate, cyclopentyl methacrylate, 2~ethoxyethyl methacrylate, isobornyl methacryiate, etc., as well as combinations thereof.

In one particularly desirable embodiment of the present invention, the poiyepoxide is a terpoiymer formed from an epoxy-functional (meth)acry!ic monomeric component, a-olefin monomeric component, and non-epoxy functional (meth)acrylic monomeric component. For example, the poiyepoxide may be poly{ethylene-co-methylacrylate-co-glycidyi methacrylate), which has the following structure:

wherein, x, y, and z are 1 or greater.

The epoxy functional monomer may be formed into a polymer using a variety of known techniques. For example, a monomer containing polar functional groups may be grafted onto a polymer backbone to form a graft copolymer. Such grafting techniques are well known in the art and described, for instance, in U.S. Patent No. 5,179,184. In other embodiments, a monomer containing epoxy functional groups may be copolymerized with a monomer to form a block or random copolymer using known free radical polymerization techniques, such as high pressure reactions, Ziegler-Natta catalyst reaction systems, single site catalyst (e.g.. metallocene) reaction systems, etc.

The relative portion of the monomeric component(s) may be selected to achieve a balance between epoxy-reacfivity and melt flow rate. More particularly, high epoxy monomer contents can result in good reactivity with the matrix polymer, but too high of a content may reduce the melt flow rate to such an extent that the poiyepoxide adversely impacts the melt strength of the poiymer blend. Thus, in most embodiments, the epoxy-functional (rneth)acrylic monomer(s) constitute from about 1 wt.% to about 25 wt.%, in some embodiments from about 2 wt.% to about 20 wt.%, and in some embodiments, from about 4 wt.% to about 15 wt.% of the copolymer. The a-olefin monomer(s) may likewise constitute from about 55 wt.% to about 95 wt.%, in some embodiments from about 80 wt.% to about 90 wt.%, and in some embodiments, from about 85 wt.% to about 85 wt.% of the copolymer. When employed, other monomeric components (e.g., non-epoxy functional (meth)acrylic monomers) may constitute from about 5 wt.% to about 35 wt.%, in some embodiments from about 8 wt.% to about 30 wt.%, and in some

embodiments, from about 10 wt.% to about 25 wt.% of the copolymer. One specific example of a suitable polyepoxide that may be used in the present

Invention is commercially available from Arkema under the name LOTADER® AX8950 or AX8900. LOTADER® AX8950, for instance, has a melt flow rate of 70 to 100 g/10 min and has a glycidyl methacrylate monomer content of 7 wt.% to 11 wt.%, a methyl acryiate monomer content of 13 wt.% to 17 wt.%, and an ethylene monomer content of 72 wt.% to 80 wt.%. Another suitable polyepoxide is commercially available from DuPont under the name ELVALOY© PTW, which is a terpo!ymer of ethylene, butyl acryiate, and glycidyl methacrylate and has a melt flow rate of 12 g/10 min.

In addition to controlling the type and relative content of the monomers used to form the polyepoxide, the overall weight percentage may also be controlled to achieve the desired benefits. For example, if the modification level is too low, the desired increase in melt strength and mechanical properties may not be achieved. The present inventors have also discovered, however, that if the modification level is too high, processing may be restricted due to strong molecular interactions (e.g., crosslinking) and physical network formation by the epoxy functional groups.

Thus, the polyepoxide is typically employed in an amount of from about 0.05 wt.% to about 10 wt.%, in some embodiments from about 0.1 wt.% to about 8 wt.%, in some embodiments from about 0.5 wt.% to about 5 wt.%, and in some

embodiments, from about 1 wt.% to about 3 wt.%, based on the weight of the matrix polymer employed in the composition. The polyepoxide may also constitute from about 0.05 wt.% to about 10 wt.%, in some embodiments from about 0.05 wt.% to about 8 wt.%, in some embodiments from about 0.1 wt.% to about 5 wt.%, and in some embodiments, from about 0.5 wt.% to about 3 wt.%, based on the total weight of the composition.

Other reactive nanoinclusion additives may also be employed in the present invention, such as oxazoline-functionalized polymers, cyanide-functionalized polymers, etc. When employed, such reactive nanoinclusion additives may be employed within the concentrations noted above for the polyepoxide. In one particular embodiment, an oxazoline-grafted poiyolefin may be employed that is a polyolefin grafted with an oxazoline ring-containing monomer. The oxazoline may include a 2-oxazoline. such as 2-vinyi-2-oxazoline (e.g., 2-isopropenyi-2~ oxazofine), 2-fatty-alkyl-2-oxazoline (e.g., obtainable from the ethano!amide of oleic acid, linoleic acid, palmitoleic acid, gadoleic acid, erucic acid and/or arachidonic acid) and combinations thereof. In another embodiment, the oxazoline may be selected from ricinoloxazoline maleinate, undecyl-2-oxazoline, soya-2- oxazoline, ricinus-2-oxazoline and combinations thereof, for example. In yet another embodiment, the oxazoline is selected from 2-isopropenyl-2-oxazoline, 2- isopropenyi-4,4~dimethyS-2-oxazoline and combinations thereof.

Nanofillers may also be employed, such as carbon black, carbon

nanotubes, carbon nanofibers, nanoclays, metal nanoparticles, nanosilica, nanoalumina, etc. Nanoclays are particularly suitable. The term "nanoc!ay" generally refers to nanoparticles of a clay material (a naturally occurring mineral, an organically modified mineral, or a synthetic nanomaterial), which typically have a platelet structure. Examples of nanoclays include, for instance, montmorillonite (2:1 layered smectite clay structure), bentonite (aluminium phyllosilicate formed primarily of montmorillonite), kaolinite (1 :1 aluminosiiicate having a platy structure and empirical formula of AbS Qs OH^), halloysite (1 :1 aluminosiiicate having a tubular structure and empirical formula of A SiaOsCQH ), etc. An example of a suitable nanoclay is Cioisite®, which is a montmorillonite nanoclay and

commercially available from Southern Clay Products, Inc. Other examples of synthethic nanoclays include but are not limited to a mixed-metal hydroxide nanoclay, layered double hydroxide nanoclay (e.g., sepiocite), laponite, hectorite, saponite, indonite, etc.

If desired, the nanoclay may contain a surface treatment to help improve compatibility with the matrix polymer (e.g., polyester). The surface treatment may be organic or inorganic, in one embodiment, an organic surface treatment is employed that is obtained by reacting an organic cation with the clay. Suitable organic cations may include, for instance, organoquaternary ammonium

compounds that are capable of exchanging cations with the clay, such as dimethyl bis[hydrogenated tallow] ammonium chloride (2M2HT), methyl benzyl

bis[hydrogenated tallow] ammonium chloride (MB2HT), methyl tris[hydrogenated tallow alkyl] chloride (M3HT), etc. Examples of commercially available organic nanoclays may include, for instance, Dellite® 43B (Laviosa Chimica of Livorno, Italy), which is a montmoriilonife clay modified with dimethyl benzyihydrogenated tallow ammonium salt. Other examples include Cloisite® 25A and Cloisite® 30B (Southern Clay Products) and Nanofil 919 (Sud Chemie). If desired, the nanofiller can be blended with a carrier resin to form a masterbatch that enhances the compatibility of the additive with the other polymers in the composition.

Particularly suitable carrier resins include, for instance, polyesters (e.g., polylactic acid, polyethylene terephthalate, etc.); polyolefins (e.g., ethylene polymers, propylene polymers, etc.); and so forth, as described in more detail above.

In certain embodiments of the present invention, multiple nanoinclusion additives may be employed in combination. For instance, a first nanoinclusion additive (e.g., polyepoxide) may be dispersed in the form of domains having an average cross-sectional dimension of from about 50 to about 500 nanometers, in some embodiments from about 60 to about 400 nanometers, and in some embodiments from about 80 to about 300 nanometers. A second nanoinclusion additive (e.g., nanofiller) may also be dispersed in the form of domains that are smaller than the first nanoinclusive additive, such as those having an average cross-sectional dimension of from about 1 to about 50 nanometers, in some embodiments from about 2 to about 45 nanometers, and in some embodiments from about 5 to about 40 nanometers. When employed, the first and/or second nanoinclusion additives typically constitute from about 0.05 wt.% to about 20 wt.%, in some embodiments from about 0.1 wt.% to about 10 wt.%, and in some embodiments, from about 0.5 wt.% to about 5 wt.% of the thermoplastic

composition, based on the weight of the continuous phase (matrix polymer(s)). The concentration of the first and/or second nanonclusion additives in the entire thermoplastic composition may likewise be from about 0.01 wt,% to about 15 wt.%, in some embodiments from about 0.05 wt.% to about 10 wt.%, and in some embodiments, from about 0.1 wt.% to about 8 wt.% of the thermoplastic

composition,

D. Other Components

A wide variety of ingredients may be employed in the composition for a variety of different reasons. For instance, in one particular embodiment, an interphase modifier may be employed in the thermoplastic composition to heip reduce the degree of friction and connectivity between the microinclusion additive and matrix polymer, and thus enhance the degree and uniformity of debonding. In this manner, the pores can become distributed in a more homogeneous fashion throughout the composition. The modifier may be in a liquid or semi-solid form at room temperature (e.g., 25°C) so that it possesses a relatively low viscosity, allowing it to be more readily incorporated info the thermoplastic composition and to easily migrate to the po!ymer surfaces. In this regard, the kinematic viscosity of the interphase modifier is typically from about 0,7 to about 200 centistokes ("cs"), in some embodiments from about 1 to about 100 cs, and in some embodiments, from about 1.5 to about 80 cs, determined at 40°C. In addition, the interphase modifier is also typically hydrophobic so that it has an affinity for the microinclusion additive, for example, resulting in a change in the interfacial tension between the matrix polymer and the additive. By reducing physical forces at the interfaces between the matrix polymer and the microinclusion additive, it is believed that the low viscosity, hydrophobic nature of the modifier can help facilitate debonding. As used herein, the term "hydrophobic" typically refers to a material having a contact angle of water in air of about 40° or more, and in some cases, about 60° or more. In contrast, the term ^"hydrophilic" typically refers to a material having a contact angle of water in air of less than about 40°. One suitable test for measuring the contact angle is ASTM D5725-99 (2008).

Suitable hydrophobic, low viscosity interphase modifiers may include, for instance, silicones, silicone-polyether copolymers, aliphatic polyesters, aromatic polyesters, alkylene glycols (e.g., ethylene glycol, diethylene glycol, triethylene glycol, tetraethyiene glycol, propylene glycol, polyethylene glycol, polypropylene glycol, polybutylene glycol, etc.), alkane diols (e.g., 1 ,3-propanedioi, 2,2-dimethyi- 1 ,3-propanediol, 1,3-butanediol, 1 ,4-butanediol, 1 ,5-pentanedioi, 1 ,6-hexanediol, 2,2,4-trimethyi-1 ,6 hexanediol, 1,3-cyciohexanedimethanol, 1 ,4- cyclohexanedimethanol, 2,2,4,4-tetramethyM .3-cyclobutanediol, etc.), amine oxides (e.g.. octy!dimethylamine oxide), fatty acid esters, fatty acid amides (e.g., oieamide, erucamide, stearamide, ethylene bis(stearamide), , etc.), mineral, and vegetable oils, and so forth. One particularly suitable liquid or semi-solid is polyether polyol, such as commercially available under the trade name Pluriol® W! from BASF Corp, Another suitable modifier is a partially renewable ester, such as commercially available under the trade name HALLGREEN® S from Hallstar.

When employed, the interphase modifier may constitute from about 0.1 wt.% to about 20 wt.%, in some embodiments from about 0.5 wt.% to about 15 wt.%, and in some embodiments, from about 1 wt.% to about 10 wt.% of the thermoplastic composition, based on the weight of the continuous phase (matrix poiymer(s)). The concentration of the interphase modifier in the entire

thermoplastic composition may likewise constitute from about 0.05 wt.% to about 20 wt.%, in some embodiments from about 0.1 wt.% to about 15 wt.%, and in some embodiments, from about 0.5 wt.% to about 10 wt.%.

When employed in the amounts noted above, the interphase modifier has a character that enables it to readily migrate to the interfacial surface of the polymers and facilitate debonding without disrupting the overall melt properties of the thermoplastic composition. For example, the interphase modifier does not typically have a plasticizing effect on the polymer by reducing its glass transition

temperature. Quite to the contrary, the present inventors have discovered that the glass transition temperature of the thermoplastic composition may be substantially the same as the initial matrix polymer. In this regard, the ratio of the giass temperature of the composition to that of the matrix polymer is typically from about 0.7 to about 1.3, in some embodiments from about 0.8 to about 1.2, and in some embodiments, from about 0.9 to about 1.1. The thermoplastic composition may, for example, have a glass transition temperature of from about 35°C to about 80°C, in some embodiments from about 40°C to about 80°C, and in some embodiments, from about 50°C to about 85°C. The melt flow rate of the

thermoplastic composition may also be similar to that of the matrix polymer. For example, the melt flow rate of the composition (on a dry basis) may be from about 0.1 to about 70 grams per 10 minutes, in some embodiments from about 0.5 to about 50 grams per 10 minutes, and in some embodiments, from about 5 to about 25 grams per 10 minutes, determined at a load of 2180 grams and at a

temperature of 190°C.

Compatibilizers may also be employed that improve interfaciaS adhesion and reduce the interfacial tension between the domain and the matrix, thus allowing the formation of smaller domains during mixing. Examples of suitable compatibilizers may include, for instance, copolymers functionalized with epoxy or maleic anhydride chemical moieties. An example of a maleic anhydride

compatibilizer is polypropyiene-grafted-maieic anhydride, which is commercially available from Arkema under the trade names Orevac™ 18750 and Orevac™ CA 100. When employed, compatibilizers may constitute from about 0.05 wt.% to about 10 wt.%, in some embodiments from about 0.1 wt.% to about 8 wt.%, and in some embodiments, from about 0.5 wt.% to about 5 wt.% of the thermoplastic composition, based on the weight of the continuous phase matrix.

Other suitable materials that may also be used in the thermoplastic composition, such as catalysts, antioxidants, stabilizers, surfactants, waxes, solid solvents, fillers, nucleating agents (e.g., calcium carbonate, etc.), particulates, and other materials added to enhance the processability and mechanical properties of the thermoplastic composition. Nevertheless, one beneficial aspect of the present invention is that good properties may be provided without the need for various conventional additives, such as blowing agents (e.g., chlorofluorocarbons, hydrochlorofiuorocarbons, hydrocarbons, carbon dioxide, supercritical carbon dioxide, nitrogen, etc.) and plasticizers (e.g., solid or semi-solid polyethylene glycol), in fact, the thermoplastic composition may be generally free of blowing agents and/or plasticizers. For example, blowing agents and/or plasticizers may be present in an amount of no more than about 1 wt.%, in some embodiments no more than about 0.5 wt.%, and in some embodiments, from about 0.001 wt.% to about 0.2 wt.% of the thermoplastic composition. Further, due to its stress whitening properties, as described in more detail below, the resulting composition may achieve an opaque color (e.g., white) without the need for conventional pigments, such as titanium dioxide. In certain embodiments, for example, pigments may be present in an amount of no more than about 1 wt.%, in some embodiments no more than about 0.5 wt.%, and in some embodiments, from about 0.001 wt.% to about 0.2 wt.% of the thermoplastic composition. II· Polymeric Material

The polymeric material .of the present invention may be formed by drawing the thermoplastic composition, which may include the matrix polymer,

microinclusion additive, nanoinclusion additive, as well as other optional components. To form the initial thermoplastic composition, the components are typically blended together using any of a variety of known techniques. In one embodiment, for example, the components may be supplied separately or in combination. For instance, the components may first be dry mixed together to form an essentially homogeneous dry mixture, and they may likewise be supplied either simultaneously or in sequence to a melt processing device that dispersiveiy blends the materials. Batch and/or continuous melt processing techniques may be employed. For example, a mixer/kneader, Banbury mixer, Parrel continuous mixer, single-screw extruder, twin-screw extruder, roll mill, etc., may be utilized to blend and melt process the materials. Particularly suitable melt processing devices may be a co-rotating, twin-screw extruder (e.g., ZSK-30 extruder available from Werner & Pfleiderer Corporation of Ramsey, New Jersey or a Thermo

Prism™ USALAB 18 extruder available from Thermo Electron Corp., Stone, England). Such extruders may include feeding and venting ports and provide high intensity distributive and dispersive mixing. For example, the components may be fed to the same or different feeding ports of the twin-screw extruder and melt blended to form a substantially homogeneous melted mixture, if desired, other additives may also be injected into the polymer melt and/or separately fed into the extruder at a different point along its length.

Regardless of the particular processing technique chosen, the resulting melt blended composition may contain micro-scale domains of the microinclusion additive and nano-scale domains of the nanoinclusion additive as described above. The degree of shear/pressure and heat may be controlled to ensure sufficient dispersion, but not so high as to adversely reduce the size of the domains so that they are incapable of achieving the desired properties. For example, blending typically occurs at a temperature of from about 180°C to about 300X, in some embodiments from about 185°C to about 250°C, and in some embodiments, from about 190°C to about 240°C. Likewise, the apparent shear rate during melt processing may range from about 10 seconds^"1 to about 3000 seconds^"1, in some embodiments from about 50 seconds^"1 to about 2000 seconds^" ¹ , and in some embodiments, from about 100 seconds^"1 to about 1200 seconds^"1, The apparent shear rate may be equai to Q/nR³, where Q is the volumetric flow rate ("m³/s") of the poiymer melt and R is the radius ("m") of the capillary (e.g., extruder die) through which the melted polymer flows. Of course, other variables, such as the residence time during melt processing, which is inversely proportional to throughput rate, may also be controlled to achieve the desired degree of homogeneity.

To achieve the desired shear conditions (e.g., rate, residence time, shear rate, melt processing temperature, etc.), the speed of the extruder screw(s) may be selected with a certain range. Generally, an increase in product temperature is observed with increasing screw speed due to the additional mechanical energy input into the system. For example, the screw speed may range from about 50 to about 600 revolutions per minute ("rpm"), in some embodiments from about 70 to about 500 rpm, and in some embodiments, from about 100 to about 300 rpm. This may result in a temperature that is sufficiently high to disperse the microinciusion additive without adversely impacting the size of the resulting domains. The melt shear rate, and in turn the degree to which the additives are dispersed, may also be increased through the use of one or more distributive and/or dispersive mixing elements within the mixing section of the extruder. Suitable distributive mixers for single screw extruders may include, for instance, Saxon, Dulmage, Cavity Transfer mixers, etc. Likewise, suitable dispersive mixers may include Blister ring,

Leroy/Maddock, CRD mixers, etc. As is well known in the art, the mixing may be further improved by using pins in the barrel that create a folding and reorientation of the poiymer melt such as those used in Buss Kneader extruders, Cavity

Transfer mixers, and Vortex Intermeshing Pin (VIP) mixers.

Once blended, the porous network structure may be introduced by drawing the composition in the longitudinal direction (e.g., machine direction), transverse direction (e.g., cross-machine direction), etc., as well as combinations thereof. To perform the desired drawing, the thermoplastic composition may be formed into a precursor shape, drawn, and thereafter converted into the desired material (e.g., film, fiber, etc.). In one embodiment, the precursor shape may be a film having a thickness of from about 1 to about 5000 micrometers, in some embodiments from about 2 to about 4000 micrometers, in some embodiments from about 5 to about 2500 micrometers, and in some embodiments, from about 10 to about 500 micrometers. As an alternative to forming a precursor shape, the thermoplastic composition may also be drawn in situ as it is being shaped into the desired form for the polymeric material, in one embodiment, for example, the thermoplastic composition may be drawn as it is being formed into a film or fiber.

Regardless, various drawing techniques may be employed, such as aspiration (e.g., fiber draw units), tensile frame drawing, biaxial drawing, multi-axial drawing, profile drawing, vacuum drawing, etc. In one embodiment, for example, the composition is drawn with a machine direction orienter ("MDO"), such as commercially available from Marshall and Willams, Co. of Providence, Rhode Island. MDO units typically have a plurality of drawing rolls (e.g., from 5 to 8) which progressively draw and thin the film in the machine direction. The

composition may be drawn in either single or multiple discrete drawing operations, it should be noted that some of the rolls in an MDO apparatus may not be operating at progressively higher speeds. To draw the composition in the manner described above, it is typically desired that the rolls of the MDO are not heated. Nevertheless, if desired, one or more rolls may be heated to a slight extent to facilitate the drawing process so long as the temperature of the composition remains below the ranges noted above.

The degree of drawing depends in part of the nature of the material being drawn (e.g., fiber or film), but is generally selected to ensure that the desired porous network is achieved. In this regard, the composition is typically drawn {e.g., in the machine direction) to a draw ratio of from about 1.1 to about 3.5, in some embodiments from about 1 .2 to about 3.0, and in some embodiments, from about 1 .3 to about 2.5. The draw ratio may be determined by dividing the length of the drawn material by its length before drawing. The draw rate may also vary to help achieve the desired properties, such as within the range of from about 5% to about 1500% per minute of deformation, in some embodiments from about 20% to about 1000% per minute of deformation, and in some embodiments, from about 25% to about 850% per minute of deformation. The composition is generally kept at a temperature below the glass temperature of the matrix polymer and

microinclusion additive during drawing. Among other things, this helps to ensure that the polymer chains are not altered to such an extent that the porous network becomes unstable. For example, the composition may be drawn at a temperature that is at least about 10^oC, in some embodiments at least about 20°C, and in some embodiments, at least about 30°C below the glass transition temperature of the matrix polymer. For example, the composition may be drawn at a temperature of from about 0°C to about 5G°C, in some embodiments from about 15°C to about 40°C, and in some embodiments, from about 20°C to about 30°C. Although the composition is typically drawn without the application of external heat (e.g., heated rolls), such heat might be optionally employed to improve processability, reduce draw force, increase draw rates, and improve fiber uniformity.

Drawing in the manner described above can result in the formation of pores that have a "nano-scale" dimension ("nanopores"). For example, the nanopores may have an average cross-sectional dimension of about 800 nanometers or less, in some embodiments from about 1 to about 500 nanometers, in some

embodiments from about 5 to about 450 nanometers, in some embodiments from about 5 to about 400 nanometers, and in some embodiments, from about 10 to about 100 nanometers. Micropores may also be formed at and around the micro- scale domains during drawing that have an average cross-sectional dimension of from about 0.5 to about 30 micrometers, in some embodiments from about 1 to about 20 micrometers, and in some embodiments, from about 2 micrometers to about 15 micrometers. The micropores and/or nanopores may have any regular or irregular shape, such as spherical, elongated, etc. In certain cases, the axial dimension of the micropores and/or nanopores may be larger than the cross- sectional dimension so that the aspect ratio {the ratio of the axial dimension to the cross-sectiona! dimension) is from about 1 to about 30, in some embodiments from about 1.1 to about 15, and in some embodiments, from about 1 .2 to about 5. The "axial dimension" is the dimension in the direction of the major axis (e.g., length), which is typically in the direction of drawing.

The present inventors have also discovered that the pores (e.g.,

micropores, nanopores, or both) can be distributed in a substantially homogeneous fashion throughout the material. For example, the pores may be distributed in columns that are oriented in a direction generally perpendicular to the direction in which a stress is applied. These columns may be generally parallel to each other across the width of the material. Without intending to be limited by theory, it is believed that the presence of such a homogeneously distributed porous network can result in a high thermal resistance as well as good mechanical properties (e.g., energy dissipation under load and impact strength). This is in stark contrast to conventional techniques for creating pores that involve the use of blowing agents, which tend to result in an uncontrolled pore distribution and poor mechanical properties. Notably, the formation of the porous network by the process described above does not necessarily result in a substantial change in the cross-sectional size (e.g., width) of the material. In other words, the material is not substantially necked, which may allow the material to retain a greater degree of strength properties.

In addition to forming a porous network, drawing can also significantly increase the axial dimension of the micro-scale domains so that they have a generally linear, elongated shape. For example, the elongated micro-scale domains may have an average axial dimension that is about 10% or more, in some embodiments from about 20% to about 500%, and in some embodiments, from about 50% to about 250% greater than the axial dimension of the domains prior to drawing. The axial dimension after drawing may, for instance, range from about 0.5 to about 250 micrometers, in some embodiments from about 1 to about 100 micrometers, in some embodiments from about 2 to about 50 micrometers, and in some embodiments, from about 5 to about 25 micrometers. The micro-scale domains may also be relatively thin and thus have a small cross-sectional dimension, such as from about 0.05 to about 50 micrometers, in some

embodiments from about 0.2 to about 10 micrometers, and in some embodiments, from 0.5 to about 5 micrometers. This may result in an aspect ratio for the first domains (the ratio of the axial dimension to the cross-sectional dimension) of from about 2 to about 150, in some embodiments from about 3 to about 100, and in some embodiments, from about 4 to about 50.

As a result of the porous and elongated domain structure, the present inventors have discovered that the resulting polymeric material can expand uniformly in volume when drawn in longitudinal direction, which is reflected by a low "Poisson coefficient", as determined according to the following equation:

PO!SSOn COeffici&nt Etransverse / E/ongitudinal where E_transverse is the transverse deformation of the material and Eiongitudinai is the longitudinal deformation of the material. More particularly, the Poisson coefficient of the material can be approximately 0 or even negative. For example, the Poisson coefficient may be about 0.1 or less, in some embodiments about 0.08 or less, and in some embodiments, from about -0,1 to about 0.04. When the Poisson coefficient is zero, there is no contraction in transverse direction when the material is expanded in the longitudinal direction. When the Poisson coefficient is negative, the transverse or lateral dimensions of the material are also expanding when the material is drawn in the longitudinal direction. Materials having a negative Poisson coefficient can thus exhibit an increase in width when drawn in the longitudinal direction, which can result in increased energy absorption in the cross direction.

The polymeric material of the present invention may generally have a variety of different forms depending on the particular application, such as films, fibrous materials, molded articles, profiles, etc.. as well as composites and laminates thereof, for use in building insulation. In one embodiment, for example, the polymeric material is in the form of a film or layer of a film. Multilayer films may contain from two (2) to fifteen (15) layers, and in some embodiments, from three (3) to twelve (12) layers. Such multilayer films normally contain at least one base layer and at least one additional layer (e.g., skin layer), but may contain any number of layers desired. For example, the multilayer film may be formed from a base layer and one or more skin layers, wherein the base layer and/or skin !ayer(s) are formed from the polymeric material of the present invention. It should be understood, however, that other polymer materials may also be employed in the base layer and/or skin layer(s), such as polyolefin polymers.

The thickness of the film may be relatively small to increase flexibility. For example, the film may have a thickness of from about 1 to about 200 micrometers, in some embodiments from about 2 to about 150 micrometers, in some

embodiments from about 5 to about 100 micrometers, and in some embodiments, from about 10 to about 80 micrometers. Despite having such a small thickness, the film may nevertheless be able to retain good mechanical properties during use. For example, the film may be relatively ductile. One parameter that is indicative of the ductility of the film is the percent elongation of the film at its break point, as determined by the stress strain curve, such as obtained in accordance with ASTM Standard D838-10 at 23°G, For example, the percent elongation at break of the film in the machine direction (" D") may be about 10% or more, in some embodiments about 50% or more, in some embodiments about 80% or more, and in some embodiments, from about 100% to about 600%. Likewise, the percent elongation at break of the film in the cross-machine direction ("CD") may be about 15% or more, in some embodiments about 40% or more, in some embodiments about 70% or more, and in some embodiments, from about 100% to about 400%. Another parameter that is indicative of ductility is the tensile modulus of the film, which is equal to the ratio of the tensile stress to the tensile strain and is determined from the slope of a stress-strain curve. For example, the film typically exhibits a MD and/or CD tensile modulus of about 2500 egapascals ("MPa") or less, in some embodiments about 2200 MPa or less, in some embodiments from about 50 MPa to about 2000 MPa, and in some embodiments, from about 100 MPa to about 1000 MPa. The tensile modulus may be determined in accordance with ASTM D638-10 at 23°C.

Although the film is ductile, it can still be relatively strong. One parameter that is indicative of the relative strength of the film is the ultimate tensile strength, which is equal to the peak stress obtained in a stress-strain curve, such as obtained in accordance with ASTM Standard D638-10. For example, the film may exhibit an MD and/or CD peak stress of from about 5 to about 85 MPa, in some embodiments from about 10 MPa to about 80 MPa, and in some embodiments, from about 20 MPa to about 55 MPa. The film may also exhibit an MD and/or CD break stress of from about 5 MPa to about 60 MPa, in some embodiments from about 10 MPa to about 50 MPa, and in some embodiments, from about 20 MPa to about 45 MPa. The peak stress and break stress may be determined in accordance with ASTM D638-10 at 23°C.

in addition to a film, the polymeric material may also be in the form of a fibrous material or a layer or component of a fibrous material, which can include individual staple fibers or filaments (continuous fibers), as well as yarns, fabrics, etc. formed from such fibers. Yarns may include, for instance, multiple staple fibers that are twisted together ("spun yarn"), filaments laid together without twist ("zero-twist yarn"), filaments laid together with a degree of twist, single filament with or without twist ("monofilament"), eta. The yarn may or may not be texturized. Suitable fabrics may likewise include, for instance, woven fabrics, knit fabrics, nonwoven fabrics (e.g., spunbond webs, meltbiown webs, bonded carded webs, wet-laid webs, airlaid webs, coform webs, hydraulically entangled webs, etc.), and so forth.

Fibers formed from the thermoplastic composition may generaiiy have any desired configuration, including monocomponent and multicomponent (e.g., sheath-core configuration, side~by-side configuration, segmented pie configuration, island-in-the-sea configuration, and so forth), !n some embodiments, the fibers may contain one or more additional polymers as a component (e.g., bicomponent) or constituent (e.g., biconstituent) to further enhance strength and other

mechanical properties. For instance, the thermoplastic composition may form a sheath component of a sheath/core bicomponent fiber, while an additional polymer may form the core component, or vice versa. The additional polymer may be a thermoplastic polymer such as polyesters, e.g., polylactic acid, polyethylene terephthaiate, polybutylene terephthaiate, and so forth; polyolefins, e.g.,

polyethylene, polypropylene, polybutylene, and so forth; polytetrafluoroethylene; polyvinyl acetate; polyvinyl chloride acetate; polyvinyl butyral; acrylic resins, e.g., polyacrylate, polymethylacrylate, polymethylmethacrylate, and so forth;

polyamides, e.g., nylon; polyvinyl chloride; polyvinylidene chloride; polystyrene; polyvinyl alcohol; and polyurethanes.

When employed, the fibers can deform upon the application of strain, rather than fracture. The fibers may thus continue to function as a load bearing member even after the fiber has exhibited substantia! elongation. In this regard, the fibers of the present invention are capable of exhibiting improved "peak elongation properties, i.e., the percent elongation of the fiber at its peak load. For example, the fibers of the present invention may exhibit a peak elongation of about 50% or more, in some embodiments about 100% or more, in some embodiments from about 200% to about 1500%, and in some embodiments, from about 400% to about 800%, such as determined in accordance with ASTM D638-10 at 23°C. Such elongations may be achieved for fibers having a wide variety of average diameters, such as those ranging from about 0.1 to about 50 micrometers, in some embodiments from about 1 to about 40 micrometers, in some embodiments from about 2 to about 25 micrometers, and in some embodiments, from about 5 to about 15 micrometers.

While possessing the ability to extend under strain, the fibers of the present invention can also remain relatively strong. For example, the fibers may exhibit a peak tensile stress of from about 25 to about 500 I legapascals ("MPa"), in some embodiments from about 50 to about 300 MPa, and in some embodiments, from about 60 to about 200 MPa, such as determined in accordance with ASTM D638- 10 at 23°C. Another parameter that is indicative of the relative strength of the fibers of the present invention is "tenacity", which indicates the tensile strength of a fiber expressed as force per unit linear density. For example, the fibers of the present invention may have a tenacity of from about 0.75 to about 6.0 grams-force ("g_f") per denier, in some embodiments from about 1.0 to about 4.5 g, per denier, and in some embodiments, from about 1.5 to about 4,0 g_f per denier. The denier of the fibers may vary depending on the desired application. Typically, the fibers are formed to have a denier per filament (i.e., the unit of linear density equal to the mass in grams per 9000 meters of fiber) of less than about 8, in some

embodiments less than about 3, and in some embodiments, from about 0.5 to about 3.

If desired, the polymeric materia! of the present invention may be subjected to one or more additional processing steps, before and/or after being drawn.

Examples of such processes include, for instance, groove roll drawing, embossing, coating, etc. In certain embodiments, the polymeric material may also be annealed to help ensure that it retains the desired shape. Annealing typically occurs at or above the glass transition temperature of the polymer matrix, such as at from about 40°to about 120°C, in some embodiments from about 50°C to about 100°C, and in some embodiments, from about 70°C to about 90°C. The polymeric material may also be surface treated using any of a variety of known techniques to improve its properties. For example, high energy beams (e.g., plasma, x-rays, e- beam, etc.) may be used to remove or reduce any skin layers, to change the surface polarity, porosity, topography, to embrittle a surface layer, etc. If desired, such surface treatment may be used before and/or drawing of the thermoplastic composition. ill- Building Insulation

As indicated above, the building insulation of the present invention can be used for a wide variety of purposes, such as for thermal insulation, acoustic insulation, impact insulation {e.g., for vibrations), fire insulation, moisture

insulation, etc., as well as combinations thereof. In certain embodiments, building insulation may be employed in a structure that is formed entirely from the polymeric material of the present invention. In other embodiments, however, the building insulation may include the polymeric material as one layer and one or more additional Iayers of material for a variety of purposes, such as for additional insulation, barrier properties, or as a covering. The additional layer(s) may include other conventional types of materials, such as polymeric foams, films or sheets, nonwoven webs, fiberglass materials, cellulosic materials, scrims, foils, etc.

Regardless of its particular construction, the building insulation may be positioned in a residential or commercial building structure so that it is adjacent to a surface of the building envelope and/or adjacent to an interior surface of the building.

Building panels, for example, may be formed from the polymeric material of the present invention and employed without limitation in the construction of foundation walls, frost wails (e.g., in buildings that have no basement),

manufactured home base curtain walls, floor systems, ceiling systems, roof systems, exterior above-grade walls, curtain walls, exterior walls in areas that use masonry exteriors, etc. Referring to Figs. 1-2, for instance, one embodiment of a building panel {e.g., foundation wall panel) that may be formed in accordance with the present invention is shown in more detail. As illustrated, a building contains interior and exterior foundation walls 10 that collectively define a foundation 12. Each foundation wall 10 is in turn defined by one or more foundation wall panels 14. In the illustration, each foundation wall panel 14 includes a bottom plate 16, an upstanding wail section 18, and a top plate 20. Each upstanding wall section 18 includes a main-run wall section 22 and uprightly-oriented reinforcing studs 23 affixed to, or integral with, the main-run wall section, regularly spaced along the length of the wall section, and extending inwardly of the inner surface of the main run wall section. In the embodiment illustrated in Fig. 1 , anchoring wedge-shaped brackets 24 are mounted to the studs at the tops and bottoms of the wall section to assist in anchoring the bottom plate and the top plate, and/or any other attachment, to the main run portion of the upstanding wail section.

As illustrated, conventional beams 26 (e.g., steel l-bearns) are mounted to the wail sections, as needed, to support spans of overlying floors. Such beams can be supported as needed by posts 28 and/or pads 30. Additional support posts can also be employed at or adjacent the ends of the beams to satisfy specific, individual load-bearing requirements of the building design. Solid reinforcing studs 23 can be used to attach the beams to respective panels of the foundation wall. As shown in Fig. 2, a main run wall section 22 is generally defined between the inner surface and the outer surface of the wall pane! 14. In accordance with one embodiment of the present invention, the wall section 22 may include the polymeric material of the present invention as building insulation 32, which provides a thermal barrier between the inwardly-facing surface of the wall and the outwardly-facing surface of the wall. Bottom plate 16 and top plate 20 can be secured to the main run section 22 with the support of wedge-shaped brackets 24 or other supporting bracket structure. The bottom plate 16 may support the foundation wall and overlying building superstructure from an underlying fabricated base, such as a concrete footer 55.

In yet other embodiments of the present invention, the building insulation of the present invention may be employed as a "housewrap" material that acts as an external sheathing for the building and is located adjacent to an external surface (e.g., wall, roof, etc.) of the building. For example, such materials may be applied to the external surface and/or to an exterior covering (e.g., siding, brick, stone, masonry, stucco, concrete veneers, etc.) prior to its installation and located adjacent thereto. Referring to Fig. 3, for instance, one embodiment is shown in which the building insulation is applied to the exterior wall. Typically, the building insulation is employed after the walls have been constructed and all sheathing and flashing details have been installed. The building insulation is preferably applied before doors and windows have been set inside framed openings and prior to the installation of the primary wall covering, in the illustrated embodiment, a first building insulation 100 is applied to the wail assembly 140. As shown, a roll of the insulation material may be unrolied. The building insulation 100 is secured to the exterior wall assembly 40 with fasteners, such as staples or cap nails. The building insulation may be trimmed around each framed opening with additional appropriate detailing applied as per window/door manufacturer and/or code standards. Once installed, an exterior covering may be applied/installed over the building insulation if so desired.

Besides insulating an external surface of a building structure, the building insulation may also be employed within the interior of a building. In such embodiments, the building insulation is typically positioned so that it is adjacent to an interior surface of the building, such as the ceiling, floor, stud wall, interior door, etc. Referring to Fig. 4, for example, one embodiment of an interior surface 250 that can be insulated in accordance with the present invention is shown, More particularly, Fig. 4 is intended to illustrate a cross-sectional view of an insulated wall cavity. In this embodiment, the surface 250 includes a wail that is attached to a pair of studs 252 and 254. Between the pair of studs 252 and 254 is a layer of the building insulation material 258 of the present invention, which is applied to the surface 250. In the embodiment illustrated in Fig. 4, the building insulation 256 is positioned directly adjacent to the surface 250. It should be understood, however, that in other embodiments, an additional type of insulation may be positioned in between the surface 250 and the building insulation 258.

The present invention may be better understood with reference to the following examples.

Test Methods

Hydrostatic Pressure Test ("Hydrohead"):

The hydrostatic pressure test is a measure of the resistance of a materia! to penetration by liquid water under a static pressure and is performed in accordance with AATCC Test Method 127-2008. The results for each specimen may be averaged and recorded in centimeters (cm). A higher value indicates greater resistance to water penetration.

Water Vapor Transmission Rate ("WVTR"):

The test used to determine the WVTR of a material may vary based on the nature of the material. One technique for measuring the WVTR value is ASTM E98/98M-12, Procedure B. Another method involves the use of INDA Test Procedure SST-70.4 (01 ). The INDA test procedure is summarized as follows. A dry chamber is separated from a wet chamber of known temperature and humidity by a permanent guard film and the sample material to be tested. The purpose of the guard film is to define a definite air gap and to quiet or still the air in the air gap while the air gap is characterized. The dry chamber, guard film, and the wet chamber make up a diffusion eel! in which the test film is sealed. The sample holder is known as the Permatran-W Mode! 100K manufactured by Mocon/Modem Controls, inc., Minneapolis, Minnesota. A first test is made of the WVTR of the guard film and the air gap between an evaporator assembly that generates 100% relative humidity. Water vapor diffuses through the air gap and the guard film and then mixes with a dry gas flow that is proportional to water vapor concentration. The electrical signal is routed to a computer for processing. The computer calculates the transmission rate of the air gap and the guard film and stores the value for further use.

The transmission rate of the guard film and air gap is stored in the computer as CalC. The sample material is then sealed in the test ceil. Again, water vapor diffuses through the air gap to the guard film and the test material and then mixes with a dry gas flow that sweeps the test material. Also, again, this mixture is carried to the vapor sensor. The computer then calculates the transmission rate of the combination of the air gap, the guard film, and the test material. This information is then used to calculate the transmission rate at which moisture is transmitted through the test material according to the equation:

R f test material™ R Hest materiai.guardfUm airgap^™ R guardfilm, airgap

The water vapor transmission rate ("WVTR") is then calculated as follows:

WVT

wherein,

F ~ the flow of water vapor in cm³ per minute;

Psat(T) - the density of water in saturated air at temperature T;

RH ~ the relative humidity at specified locations in the cell;

A = the cross sectional area of the cell; and

Psatfo ~ the saturation vapor pressure of water vapor at temperature T,

Conductive Properties:

Thermal conductivity (W/mK) and thermal resistance (m²K W) may be determined in accordance with ASTM E-1530-11 ("Resistance to Thermal Transmission of Materials by the Guarded Heat Flow Meter Technique") using an Anter Unitherm Mode! 2022 tester. The target test temperature may be 25°C and the applied load may be 0.17 MPa. Prior to testing, the samples may be conditioned for 40+ hours at a temperature of 23°C (+2°C) and relative humidity of 50% (+10%). Thermal admittance (W/m²K) may also be calculated by dividing 1 by the thermal resistance.

Melt Flow Rate:

The me!t flow rate ("MFR") is the weight of a polymer (in grams) forced through an extrusion rheometer orifice (0.0825-inch diameter) when subjected to a load of 2160 grams in 10 minutes, typically at 190°C, 210°C, or 230°C. Unless otherwise indicated, melt flow rate is measured in accordance with AST Test Method D1239 with a Tinius Olsen Extrusion Plastometer.

Thermal Properties:

The glass transition temperature (T_g) may be determined by dynamic mechanical analysis (DMA) in accordance with ASTM E 840-09. A Q800 instrument from TA Instruments may be used. The experimental runs may be executed in tension/tension geometry, in a temperature sweep mode in the range from -120°C to 150°C with a heating rate of 3°G/min. The strain amplitude frequency may be kept constant (2 Hz) during the test, Three (3) independent samples may be tested to get an average glass transition temperature, which is defined by the peak value of the tan δ curve, wherein tan δ is defined as the ratio of the loss modulus to the storage modulus (tan δ = E E').

The melting temperature may be determined by differential scanning calorimetry (DSC). The differential scanning calorimeter may be a DSC Q100

Differential Scanning Calorimeter, which may be outfitted with a liquid nitrogen cooling accessory and with a UNIVERSAL ANALYSIS 2000 (version 4.6.6) analysis software program, both of which are available from T.A. Instruments Inc. of New Castle, Delaware. To avoid directly handling the samples, tweezers or other tools may be used. The samples may be placed into an aluminum pan and weighed to an accuracy of 0.01 milligram on an analytical balance. A lid may be crimped over the material sample onto the pan. Typically, the resin pellets may be placed directly in the weighing pan.

The differential scanning calorimeter may be calibrated using an indium metal standard and a baseline correction may be performed, as described in the operating manual for the differential scanning calorimeter. A material sample may be placed into the test chamber of the differential scanning calorimeter for testing, and an empty pan may be used as a reference. Ail testing may be run with a 55- cubic centimeter per minute nitrogen (industrial grade) purge on the test chamber. For resin pellet samples, the heating and cooling program is a 2-cycle test that began with an equilibration of the chamber to -30°C, followed by a first heating period at a heating rate of 10°C per minute to a temperature of 200°C, followed by equilibration of the sample at 200°C for 3 minutes, followed by a first cooling period at a cooling rate of 10°C per minute to a temperature of -3G°C, followed by equilibration of the sample at -30°C for 3 minutes, and then a second heating period at a heating rate of 10^QC per minute to a temperature of 200°C. For fiber samples, the heating and cooling program may be a 1 -cycle test that begins with an equilibration of the chamber to -25⁰C, followed by a heating period at a heating rate of 10°C per minute to a temperature of 2G0°C, followed by equilibration of the sample at 200°C for 3 minutes, and then a cooling period at a cooling rate of 10°C per minute to a temperature of -30°C. All testing may be run with a 55-cubic centimeter per minute nitrogen (industrial grade) purge on the test chamber.

The results may be evaluated using the UNIVERSAL ANALYSIS 2000 analysis software program, which identifies and quantifies the glass transition temperature (T_g) of inflection, the endothermic and exothermic peaks, and the areas under the peaks on the DSC plots. The glass transition temperature may be identified as the region on the plot-Sine where a distinct change in slope occurred, and the melting temperature may be determined using an automatic inflection calculation.

Film Tensile Properties:

Films may be tested for tensile properties (peak stress, modulus, strain at break, and energy per volume at break) on a MTS Synergie 200 tensile frame. The test may be performed in accordance with AST D838-10 (at about 23°C). Film samples may be cut into dog bone shapes with a center width of 3.0 mm before testing. The dog-bone film samples may be held in place using grips on the MTS Synergie 200 device with a gauge length of 18.0 mm. The film samples may be stretched at a crosshead speed of 5.0 in/min until breakage occurred. Five samples may be tested for each film in both the machine direction (MD) and the cross direction (CD), A computer program (e.g., TestWorks 4) may be used to collect data during testing and to generate a stress versus strain curve from which a number of properties may be determined, including modulus, peak stress, elongation, and energy to break.

Fiber Tensile Propetiies:

Fiber tensile properties may be determined in accordance with ASTM 838- 10 at 23°C. For instance, individual fiber specimens may initially be shortened (e.g., cut with scissors) to 38 millimeters in length, and placed separately on a black velvet cloth. 10 to 15 fiber specimens may be collected in this manner. The fiber specimens may then be mounted in a substantially straight condition on a rectangular paper frame having external dimension of 51 millimeters x 51 millimeters and internal dimension of 25 millimeters x 25 millimeters. The ends of each fiber specimen may be operatively attached to the frame by carefully securing the fiber ends to the sides of the frame with adhesive tape. Each fiber specimen may be measured for its external, relatively shorter, cross-fiber dimension employing a conventional laboratory microscope, which may be properly calibrated and set at 40X magnification. This cross-fiber dimension may be recorded as the diameter of the individual fiber specimen. The frame helps to mount the ends of the sample fiber specimens in the upper and lower grips of a constant rate of extension type tensile tester in a manner that avoids excessive damage to the fiber specimens.

A constant rate of extension type of tensile tester and an appropriate load cell may be employed for the testing. The load cell may be chosen (e.g., 10N) so that the test value fails within 10-90% of the full scale load. The tensile tester (i.e., MTS SYNERGY 200) and load cell may be obtained from MTS Systems

Corporation of Eden Prairie, Michigan. The fiber specimens in the frame assembly may then be mounted between the grips of the tensile tester such that the ends of the fibers may be operatively held by the grips of the tensile tester. Then, the sides of the paper frame that extend parallel to the fiber length may be cut or otherwise separated so that the tensile tester applies the test force only to the fibers. The fibers may be subjected to a puii test at a pull rate and grip speed of 12 inches per minute. The resulting data may be analyzed using a TESTWORKS 4

The tenacity valu es may be express* 3d in terms of gram-fc irce per denier.

Peak elongation (% strain at break) and peak stress may also be measured.

Expansion Ratio, Density, and Percent Pore Volume:

To determine expansion ratio, density, and percent pore volume, the width (Wi) and thickness (Ti) of the specimen may be initially measured prior to drawing. The length ( ) before drawing may also be determined by measuring the distance between two markings on a surface of the specimen. Thereafter, the specimen may be drawn to initiate voiding. The width (W_f), thickness (T_f). and length (L) of the specimen may then be measured to the nearest 0.01 mm utilizing Digimatic Caliper (Mitutoyo Corporation). The vo!ume (Vj) before drawing may be calculated by Wi x Tj x Lj = V|. The volume (V_f) after drawing may also be calculated by W_f x T_f x L_f = V_f. The expansion ratio (Φ) may be calculated by Φ = V_f/V,; the density (P_f) of was calculated by: P_f = Ρ,/Φ, where P, is density of precursor material; and the percent pore volume (% V_v) may be calculated by: %V_V = (1 - 1/ Φ) x 100. Moisture Content:

Moisture content may be determined using an Arizona Instruments

Computrac Vapor Pro moisture analyzer (Model No. 3100) in substantial accordance with ASTM D 7191-05, which is incorporated herein in its entirety by reference thereto for all purposes. The test temperature (§X2.1 .2) may be 13Q°C, the sample size (§X2.1.1) may be 2 to 4 grams, and the vial purge time (§X2.1.4) may be 30 seconds. Further, the ending criteria (§X2.1.3) may be defined as a "prediction" mode, which means that the test is ended when the built-in

programmed criteria (which mathematically calculates the end point moisture content) is satisfied. .EXAMPLE ...1

The ability to form a polymeric material for use in building insulation was demonstrated. Initially, a blend of 85.3 wt.% poiylactic acid (PLA 8201 D,

Natureworks©), 9.5 wt.% of a microinclusion additive, 1.4 wt.% of a nanoinclusion additive, and 3.8 wt.% of an interfacia! modifier was demonstrated. The

microinclusion additive was Vistamaxx™ 2120 (ExxonMobil), which is a polyolefin copolymer/elastomer with a melt flow rate of 29 g/10 min (190X, 2160 g) and a density of 0.866 g/cm³. The nanoinclusion additive was pofy(ethylene-co-methyl acryiate-co-giycidyl methacrySate) (Lotader® AX8900, Arkema) having a melt flow rate of 5-6 g/ 0 min (190°C/2160 g), a glycidyl methacrylate content of 7 to 1 wt.%, methyl acrylate content of 13 to 17 wt.%, and ethylene content of 72 to 80 wt.%, the internal interfacia! modifier was PLURIOL®WI 285 Lubricant from BASF which is a Poiyalkylene Glycol Functional Fluids. The polymers were fed into a co- rotating, twin-screw extruder (ZSK-30, diameter of 30 mm, length of 1328 millimeters) for compounding that was manufactured by Werner and Pfleiderer Corporation of Ramsey, New Jersey. The extruder possessed 14 zones, numbered consecutively 1-1 from the feed hopper to the die. The first barrel zone #1 received the resins via gravimetric feeder at a total throughput of 15 pounds per hour. The PLURIOL® WI285 was added via injector pump info barrel zone #2. The die used to extrude the resin had 3 die openings (6 millimeters in diameter) that were separated by 4 millimeters. Upon formation, the extruded resin was cooled on a fan~cooied conveyor belt and formed into pellets by a Conair pelletizer. The extruder screw speed was 200 revolutions per minute ("rpm"). The pellets were then flood fed into a signal screw extruder heated to a temperature of 212°C where the molten blend exited through 4.5 inch width slit die and drawn to a film thickness ranging from 0.54 to 0.58 mm.

EXAMPLE^

The sheet produced in Example 1 was cut to a 6" length and then drawn to 100% elongation using a MTS 820 hydraulic tensile frame in tensile mode at 50 mm/min. EXAMPLE 3

The sheet produced in Example 1 was cut to a 8" length and then drawn to 150% elongation using a MTS 820 hydraulic tensile frame in tensile mode at 50 mm/min,

EXAMPLE 4

The sheet produced in Example 1 was cut to a 8" length and then drawn to 200% elongation using a MTS 820 hydraulic tensile frame in tensile mode at 50 mm/min.

The thermal properties of Examples 1-4 were then determined. The results are set forth in the table below,

EXAMPLE 5

Pellets were formed as described in Example 1 and then flood fed into a Rheomix 252 single screw extruder with a L/D ratio of 25:1 and heated to a temperature of 212°C where the molten blend exited through a Haake 6 inch width s cast film die and drawn to a film thickness ranging from 39.4 μητϊ to 50.8 μηι via Haake take-up roll. The film was drawn in the machine direction to a longitudinal deformation of 160% at a pull rate of 50 mm/min (deformation rate of 67%/min) via MTS Synergie 200 tensile frame with grips at a gage length of 75 mm.

Films were formed as described in Example 5, except that the film was also stretched in the cross-machine direction to a deformation of 100% at a pull rate of 50 mm/min (deformation rate of 1 0%/min) with grips at a gage length of 50 mm.

Various properties of the films of Examples 5-8 were tested as described above. The results are set forth below in Tables 1-2. Tabte 1 : Film Properties

Average Expansion Percent Void Volume Density | WVT (g/m²*24 Ex.

Thickness (pm) Ratio (Φ) (%V_V) (g/cm³) ! hrs.)

! 5 41.4 1.82 45 [ 0,65 j 5453

1: 6 34.0 ί 2.13 : 53 : 0,56 i 4928

Table 2: Tensife Properties

Pellets were formed as described in Example 1 and then flood fed into a signal screw extruder heated to a temperature of 212°C, where the molten blend exited through 4.5 inch width slit die and drawn to a film thickness ranging from 36 μιη to 54 μηχ The films were stretched in the machine direction to about 100% to initiate cavitation and void formation. The morphology of the films was analyzed by scanning electron microscopy (SEM) before and after stretching. The results are shown in Figs. 5-8. As shown in Figs. 5-6, the microindusion additive was initially dispersed in domains having an axial size (in machine direction) of from about 2 to about 30 micrometers and a transverse dimension (in cross-machine direction) of from about 1 to about 3 micrometers, while the nanoinclusion additive was initially dispersed as spherical or spheroidal domains having an axial size of from about 100 to about 300 nanometers. Figs. 7-8 show the film after stretching. As indicated, pores formed around the microindusion and nanoinclusion additives. The micropores formed around the microindusion additive generally had an elongated or slit-like shape with a broad size distribution ranging from about 2 to about 20 micrometers in the axial direction. The nanopores associated with the nanoinclusion additive generally had a size of from about 50 to about 500 nanometers. EXAMPLE 8

The compounded pellets of Example 7 were dry blended with another nanoinclusion additive, which was a haiioisite clay masterbatch ( acroComp

NH-731-36, MacroM) containing 22 wt.% of a styrenic copolymer modified nanociay and 78 wt.% polypropylene (Exxon Mobil 3155). The mixing ratio was 90 wt.% of the pellets and 10 wt.% of the clay masterbatch, which provided a total clay content of 2.2%. The dry blend was then flood fed into a signal screw extruder heated to a temperature of 212°C, where the molten blend exited through 4.5 inch width slit die and drawn to a film thickness ranging from 51 to 58 Mm. The films were stretched in the machine direction to about 100% to initiate cavitation and void formation.

The morphology of the films was analyzed by scanning electron microscopy (SE ) before and after stretching. The results are shown in Figs. 9-12. As shown in Figs. 9-10, some of the nanociay particles (visible as brighter regions) became dispersed in the form of very small domains - i.e., axial dimension ranging from about 50 to about 300 nanometers. The masterbatch itself also formed domains of a micro-scale size (axial dimension of from about 1 to about 5 micrometers). Also, the microinclusion additive (Vistamaxx™) formed elongated domains, while the nanoinclusion additives (Lotader®, visible as ultrafine dark dots and nanociay masterbatch, visible as bright platelets) formed spheroidal domains. The stretched film is shown in Figs. 11-12. As shown, the voided structure is more open and demonstrates a broad variety of pore sizes. In addition to highly elongated micropores formed by the microinclusions (Vistamaxx™), the nanociay

masterbatch inclusions formed more open spheroidal micropores with an axial size of about 10 microns or less and a transverse size of about 2 microns. Spherical nanopores are also formed by the nanoinclusion additives (Lotader® and nanociay particles).

Various tensile properties (machine direction) of the films of Example 1 and 2 were also tested. The results are provided below in Table 3. Talbie 3

As shown, the addition of the nanoclay filler resulted in a slight increase in break stress and a significant increase in elongation at break.

EXAMPLE J

The ability to form fibers for use in building insulation was demonstrated. Initially, a precursor blend was formed from 91.8 wt.% isotactic propylene homopolymer (M3661 , melt flow rate of 14 g/10 at 210°C and melting temperature of 150°C, Total Petrochemicals), 7.4 wt.% poiylactic acid (PLA 6252, melt flow rate of 70 to 85 g/10 min at 210°C, Natureworks®), and 0.7 wt.% of a poiyepoxide. The poiyepoxide was poly(ethyiene~co~methyi acrylate-co-glycidyl methacrylate) (LOTADER® AX8900, Arkema) having a melt flow rate of 6 g/10 min (190°C/2160 g), a glycidyl methacrylate content of 8 wt.%, methyl acryiate content of 24 wt.%. and ethylene content of 68 wt.%. The components were compounded in a co- rotating twin-screw extruder (Werner and Pfleiderer ZSK-30 with a diameter of 30 mm and a L/D~44). The extruder had seven heating zones. The temperature in the extruder ranged from 180°C to 220°C. The polymer was fed gravimetrically to the extruder at the hoper at 15 pounds per hour and the liquid was injected into the barrel using a peristaltic pump. The extruder was operated at 200 revolutions per minute (RPM). In the last section of the barrel (front), a 3~hole die of 6 mm in diameter was used to form the extrudate. The extrudate was air-cooled in a conveyor belt and pelletized using a Conair Pelletizer.

Fiber was then produced from the precursor blend using a Davis-Standard fiber spinning line equipped with a 0.75~inch single screw extruder and 18 hole spinneret with a diameter of 0.6 mm. The fibers were collected at different draw down ratios. The take up speed ranged from 1 to 1000 m/min. The temperature of the extruder ranged from 175^CC to 220°C. The fibers were stretched in a tensile tester machine at 300 mm/min up to 400% elongation at 25°C. To analyze the material morphology, the fibers were freeze fractured in liquid nitrogen and analyzed via Scanning Electron Microscope Jeoi 6490LV at high vacuum. The results are shown in Fig. 13-15. As shown, spheroidal pores are formed that are elongated in the stretching direction. Both nanopores (-50 nanometers in width, -500 nanometers in length) and micropores (-0.5 micrometers in width, ~4 micrometers in length) were formed.

EXAMPLE 10.

Pel lets were f ormed as des cribed in Example " and then flood fed into a single screw extruder at 240°C, m e!ted, and passed t irough a melt pi jmp at a rate of 0.40 grams per he >le per minute through a 0.6 mm < diameter spinneret. Fibers were coile cted in fre< 3 fail (gravity only as draw force) and then tested for mechanic al propertie is at a pull rat e of 50 millimeters | Der minute. Fibe ¾rs were then cold drawn at 23°C i n a IV!TS Syn« srgie Tensile frame at a rate of 50 mm/min.

Fibers we re drawn tc > pre-defined strains of 50%, 100 %, 150%, 200% and 250%.

After drawing, the ex pansion ratio . void volume and density were calculated for various strain rates ε is s own in th ie tables below.

j Initial Initial I Initial Volume after

Strain j Length after Diameter after

I Length Diameter Volume elongation

% j :^: elongation (mm) elongation (mm)

(mm) (mm) (mm^A3) (mm^A3)

50 0.1784 1.2498 j 50.0 ji: 75 0.1811 1.9319

50 0.2047 I 1.6455 I 100.0 100 0.2051 3.3039

50 0.1691 j 1.1229 150.0 j: 125 j 0.165 2.6728

50 0.242 2.2998 j 200.0 150 j 0.1448 2.4701

50 0.1795 j 1.2653 j 250.0 175 j !Tl Q62 1.5502

j 175 0.183 1.23 18.4 1.2 : 0.98 fully necked

Fibers were formed as described in Example 10, except that they were collected at a collection roll speed of 100 meters per minute resulting in a drawn down ratio of 77, Fibers were then tested for mechanical properties at a pull rate of 50 millimeters per minute. Fibers were then cold dravm at 23°C in a MTS Synergie Tensile frame at a rate of 50 mm/min. Fibers were drawn to pre-defined strains of 50%, 100%, 150%, 200% and 250%, After drawing, the expansion ratio, void volume and density were calculated for various strain rates as shown in the tables below.

¾PLE 12

Fibers were formed as described in Example 10, except that the blend was composed of 83.7 wt.% polyiactic acid (PLA 6201 D, Natureworks®), 9.3 wt.% of Vistamaxx™ 2120, 1 .4 wt.% Lotader® AX8900, 3.7% wt.% PLUR!OL® Wl 285, and 1.9% hydrophific surfactant (Masil SF-19). The PLURIOL® WI285 and Masil SF-19 were premixed at a 2:1 (WI-285:SF-19) ratio and added via injector pump into barrel zone #2. Fibers were collected at 240°C, 0.40 ghm and under free fail

Fibers were formed as described in Example 12, except that they were collected at a collection roil speed of 100 meters per minute resulting in a drawn down ratio of 77. Fibers were then tested for mechanical properties at a pull rate of 50 millimeters per minute. Fibers were then cold drawn at 23°C in a fvTTS

Synergie Tensile frame at a rate of 50 mm/min, Fibers were drawn to pre-defined strain of 100%. After drawing, the expansion ratio, void volume and density were calculated as shown in the tables below.

EXAMPLE 14

Fibers from Example 12 were stretched in a MTS Synergie Tensile frame at a rate of 50 millimeters per minute to 250% strain, This opened up the void structure and turned the fiber white. A one inch sample was then cut from the stressed, white area of the fiber. The new fiber was then tested as described above. The density was estimated to be 0.75 grams per cubic centimeters and the pull rate for the tensile test was 305 mm/min.

EXAMPLE 15

Fibers from Example 11 were heated in an oven at 50°C for 30 minutes to anneal the fiber.

EXAMPLE 18

Fibers from Example 11 were heated in an oven at 90°C for 5 minutes to anneal the fiber and induce crystallization. The fibers of Examples 10-18 were then tested for mechanical properties at

While the invention has been described in detail with respect to the specific embodiments thereof, it will be appreciated that those skilled in the art, upon attaining an understanding of the foregoing, may readily conceive of alterations to, variations of, and equivalents to these embodiments. Accordingly, the scope of the present invention should be assessed as that of the appended claims and any equivalents thereto.

Claims

WHAT IS CLAIMED IS

1. Building insulation for use in a residential or commercial building structure, wherein the building insulation includes a porous polymeric material that is formed from a thermoplastic composition containing a continuous phase that includes a matrix polymer, wherein the poiymeric materiai exhibits a water vapor transmission rate of about 300 g/m²-24 hours or more, thermal conductivity of about 0,40 watts per meter-kelvin or less, and/or hydrohead value of about 50 centimeters or more.

2. The building insulation of claim 1 , wherein the polymeric material further comprises a microinclusion additive and nanoinclusion additive dispersed within the continuous phase in the form of discrete domains, wherein a porous network is defined in the materia! that includes a plurality of nanopores having an average cross-sectional dimension of about 800 nanometers or less.

3. Building insulation for use in a residential or commercial building structure, wherein the building insulation includes a porous polymeric material that is formed from a thermoplastic composition containing a continuous phase that includes a matrix polymer, and further wherein a microinclusion additive and nanoinclusion additive are dispersed within the continuous phase in the form of discrete domains, wherein a porous network is defined in the material that includes a plurality of nanopores having an average cross-sectional dimension of about 800 nanometers or less.

4. The building insulation of claim 3, wherein the polymeric materia! exhibits a water vapor transmission rate of about 300 g/m²~24 hours or more, thermal conductivity of about 0,40 watts per meter-kelvin or less, and/or hydrohead value of about 50 centimeters or more.

5. The building insulation of claim 2 or 3, wherein the microinclusion additive is poiymeric,

6. The building insulation of claim 5, wherein the microinciusion additive includes a polyolefin.

7. The building insulation of claim 8, wherein the polyolefin is a propylene homopolymer, propyiene/a-olefin copolymer, ethylene/a~olefin copolymer, or a combination thereof.

8. The building insulation of claim 2 or 3, wherein the ratio of the solubility parameter for the matrix polymer to the solubility parameter of the microinclusion additive is from about 0.5 to about 1.5, the ratio of the melt flow rate for the matrix polymer to the melt flow rate of the microinclusion additive is from about 0.2 to about 8, and/or the ratio of the Young's modulus elasticity of the matrix polymer to the Young's modulus of elasticity of the microindusion additive is from about 1 to about 250.

9. The building insulation of claim 2 or 3, wherein the nanoinclusion additive is polymeric.

10. The building insulation of claim 9, wherein the nanoinclusion additive is a functionalized polyolefin.

11. The building insulation of claim 9 or 10, wherein the nanoinclusion additive is reactive.

12. The building insulation of claim 11 , wherein the nanoinclusion additive is a polyepoxide.

13. The building insulation of claim 2 or 3, wherein the microinclusion additive constitutes from about 1 wt.% to about 30 wt.% of the composition, based on the weight of the continuous phase.

14. The building insulation of claim 2 or 3, wherein the nanoinclusion additive constitutes from about 0.05 wt.% to about 20 wt.% of the composition, based on the weight of the continuous phase.

15. The building insulation of claim 2 or 3, wherein the thermoplastic composition further comprises an interphase modifier.

16. The building insulation of claim 15, wherein the interphase modifier has a kinematic viscosity of from about 0.7 to about 200 centistokes, determined at a temperature of 40°C.

17. The building insulation of claim 15 or 16, wherein the interphase modifier is hydrophobic.

18. The building insulation of claims 14, 15, or 18, wherein the interphase modifier is a silicone, silicone-polyether copolymer, aliphatic polyester, aromatic polyester, alkySene glycol, alkane diol, amine oxide, fatty acid ester, or a

combination thereof.

19. The building insulation of any of claims 14 to 18, wherein the interphase modifier constitutes from about 0.1 wt.% to about 20 wt.% of the composition based on the weight of the continuous phase.

20. The building insulation of claim 2 or 3, wherein the porous network further includes micropores having an average cross-sectional dimension of from about 0.5 to about 30 micrometers.

21. The bui!ding insulation of claim 20, wherein the aspect ratio of the micropores is from about 1 to about 30.

22. The building insulation of claim 2 or 3, wherein the porous network is distributed in a substantially homogeneous fashion throughout the material.

23. The building insulation of any of the foregoing claims, wherein the nanopores are distributed in generally parallel columns.

24. The building insulation of claim 2 or 3, wherein the microinclusion additive is in the form of micro-scale domains and the nanoinciusion additive is in the form of nano-scale domains, wherein the micro-scale domains have an average cross-sectional dimension of from about 0.5 to about 250 micrometers and the nano-scale domains have an average cross-sectional dimension of from about 1 nanometer to about 500 nanometers.

25. The building insulation of any of claims 1 to 24, wherein the insulation is formed entirely from the polymeric material.

26. The building insulation of any of claims 1 to 24, further comprising an additional layer of material.

27. The building insulation of any of claims 1 to 26, wherein the insulation is in the form of a panel.

28. The building insulation of any of claims 1 to 26, wherein the insulation is in the form of a wrap.

29. The building insulation of any of the foregoing claims, wherein the total pore volume of the polymeric material is from about 15% to about 80% per cubic centimeter.

30. The building insulation of any of the foregoing claims, wherein nanopores constitute about 20 vol.% or more of the total pore volume of the polymeric materia!.

31. The building insulation of any of the foregoing claims, wherein the continuous phase constitutes from about 60 wt.% to about 99 wt.% of the thermoplastic composition.

32. The building insulation of any of the foregoing claims, wherein the matrix polymer includes a polyester or poiyolefin.

33. The building insulation of claim 32, wherein the polyester has a glass transition temperature of about 0°C or more.

34. The building insulation of claim 32 or 33, wherein the polyester includes po ylactic acid.

35. The building insulation of any of the foregoing claims, wherein the polymeric material is generally free of gaseous blowing agents.

38. The building insulation of any of the foregoing claims, wherein the thermoplastic composition has a density of about 1.2 grams per cubic centimeter or less.

37. The polymeric material of any of claims 1 to 38, wherein the polymeric material is a film or a layer of a film.

38. The polymeric material of any of claims 1 to 36, wherein the polymeric material is a fibrous material or a layer or component of a fibrous material,

39. A building structure comprising a building envelope that defines an interior, the building structure further comprising the building insulation of the any of foregoing claims, which is positioned adjacent to a surface of the building envelope, the interior, or a combination thereof.

40. The building structure of claim 39, wherein the building insulation is positioned adjacent to a surface of the building envelope.

41. The building structure of claim 40, wherein the building insulation is positioned adjacent to an exterior wall, roof, or a combination thereof.

42. The building structure of claim 41 , wherein the building insulation is also positioned adjacent to an exterior covering.

43. The building structure of claim 39, wherein the building insulation is positioned adjacent to a surface of the interior.

44. The building structure of claim 43, wherein the building insulation is positioned adjacent to an interior wall, floor, ceiling, door, or a combination thereof.