KR101258021B1 - Thermoplastic elastomer resin composition - Google Patents

Abstract

A thermoplastic elastomer resin composition is provided. The thermoplastic elastomer resin composition contains 67 to 96.7 wt% polyester elastomer resin, 3 to 30 wt% styrene resin and 0.3 to 3.0 wt% reactive additive.

Polyester, Elastomer, Resin Composition

Description

Thermoplastic elastomer resin composition {THERMOPLASTIC ELASTOMER RESIN COMPOSITION}

The present invention relates to a resin composition, and more particularly to a thermoplastic elastomer resin composition comprising a polyester-based elastomer resin, a styrene-based resin and a reactive additive.

Thermoplastic polyester-based elastomers are excellent in basic mechanical strength and heat resistance compared to other materials, but have good abrasion resistance, and thus are widely applied to industrial hoses and the like.

However, the thermoplastic polyester-based elastomer has a very high adhesiveness of the resin itself at the time of melting, so that there is a phenomenon of sticking to each other before injection of molding gas during blow molding, and thus many molding defects are generated, and the molding itself may not be severe. In order to solve these molding defects, the melt tension must be properly maintained and the surface adhesion must be reduced.

Many studies have been conducted to increase the adhesiveness of polymer materials for double injection or compatibility of polymers, but the method for lowering adhesiveness has not been greatly studied.

Korean Patent Laid-Open Publication No. 2002-0016845 discloses lubrication for reducing adhesion to the mold surface during injection molding using a blend of polycarbonate / ABS, polyamide / ABS, polycarbonate / polyethylene terephthalate or polybutylene terephthalate. Although the use of a release agent is disclosed, it is intended for release of the mold and the injection product, but not for the reduction of the tack in the resin itself.

As described above, the method using the release agent requires the use of excessive lubrication / release agent, and problems such as mold deposition may occur, resulting in poor molding and productivity.

In order to solve the above problems, the present invention provides a thermoplastic elastomer resin composition having reduced adhesiveness and excellent moldability while maintaining mechanical properties.

The thermoplastic elastomer resin composition according to embodiments of the present invention includes 67 to 96.7 wt% polyester elastomer resin, 3 to 30 wt% styrene resin, and 0.3 to 3.0 wt% reactive additive.

The polyester-based elastomer resin may be composed of a hard segment prepared by polymerizing one or more selected from aromatic dicarboxylic acid and aromatic dicarboxylate and a lower diol and a soft segment of polyalkylene oxide.

The aromatic dicarboxylic acids include terephthalic acid (TPA), isophthalic acid (IPA), 1,5-naphthalene dicarboxylic acid (1,5-NDCA), and 2,6-naphthalene dicarboxylic acid (2,6-NDCA It may include one or more selected from the group consisting of, wherein the aromatic dicarboxylate may be dimethyl isophthalate (Dimethyl Isophthalate).

The lower diol may include one or more selected from the group consisting of ethylene glycol, propylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, and 1,4-cyclohexanedimethanol. .

The poly alkylene oxide may include one or more selected from the group consisting of polyoxyethylene glyoxypropylene glycol and polyoxytetramethylene glycol.

The styrene-based polymer is a styrene-butadiene-styrene block copolymer, a styrene-butylene-styrene block copolymer, a styrene-butyene-styrene block copolymer ), Styrene-isoprene-styrene block copolymer (Styrene-Isoprene-Styrene (SIS) Block Copolymer), and styrene-butadiene rubber (Styrene-Butadiene Rubber, SBR) may be included.

The reactive additive may include one or more selected from the group consisting of compounds having functional groups of isocyanate groups, carbodiimide groups, or epoxy groups. One or more of the compounds may have the functional group at the end.

The thermoplastic elastomer resin composition may further include one or more selected from the group consisting of antioxidants, light stabilizers, lubricants, reinforcing agents and pigments.

The thermoplastic elastomer resin composition according to embodiments of the present invention may have a reduced adhesiveness and an appropriate melt tension, and may prevent the sticking phenomenon of the resin itself. The thermoplastic elastomer resin composition is capable of various moldings regardless of the molding method or mold design without harming the surface properties and mechanical properties. It can also be used to manufacture parts suitable for blow molding which can reduce molding defects.

Hereinafter, the present invention will be described in more detail with reference to the following examples. The objects, features and advantages of the present invention will be easily understood by the following embodiments. The present invention is not limited to the embodiments described herein, but may be embodied in other forms. The embodiments disclosed herein are provided so that the disclosure may be thorough and complete, and that those skilled in the art will be able to convey the spirit of the invention to those skilled in the art. Therefore, the present invention should not be limited by the following examples.

In addition, although the English letter "R" used to represent a hydrogen atom or a hydrocarbon group, etc. in the chemical formula described herein has a subscript represented by a number, the "R" is limited by such a subscript. Can not be done. "R" may independently represent a hydrogen atom or a hydrocarbon group. For example, even if two or more "Rs" have the same number of subscripts, these "Rs" may represent the same hydrocarbon group or may represent different hydrocarbon groups. In addition, even if two or more "R" have different numbers of subscripts, these "R" may represent the same hydrocarbon group or may represent a different hydrocarbon group.

The thermoplastic elastomer resin composition according to the embodiments of the present invention may include 67 to 96.7 wt% polyester elastomer resin, 3 to 30 wt% styrene resin, and 0.3 to 3.0 wt% reactive additive. . Description of each component of the said thermoplastic elastomer resin composition is as follows.

Polyester Elastomer Resin

Polyester-based elastomer resin according to embodiments of the present invention is thermoplastic, it may be composed of a hard segment and a soft segment. The hard segment may have a backbone structure in ester form that structurally forms a highly crystalline domain, and the soft segment may be a polymer polyol composed of a polymer of alcohols as a matrix. As a result, the thermoplastic elastomer resin composition may have resistance to repeated loads, impact resistance, wear resistance, and excellent tensile elongation and tensile strength.

The hard segment may be prepared by polymerizing one or more selected from aromatic dicarboxylic acids and aromatic dicarboxylates with lower diols. The aromatic dicarboxylic acid may be, for example, terephthalic acid (TPA), isophthalic acid (IPA), 1,5-naphthalene dicarboxylic acid (1,5-NDCA), or 2,6-naphthalene dicarboxylic acid (2 , 6-NDCA), and the like, but is not limited thereto. The aromatic dicarboxylate may include, for example, dimethyl isophthalate, but is not limited thereto. Preferably, dimethyl isophthalate can be used.

The lower diol may include, for example, but not limited to, ethylene glycol, propylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol or 1,4-cyclohexanedimethanol It doesn't work. Preferably, 1,4-butanediol can be used.

The soft segment may be, for example, polyalkylene oxide. The polyalkylene oxide may include, but is not limited to, for example, polyoxyethylene glyoxypropylene glycol or polyoxytetramethylene glycol. Preferably, polyoxytetramethylene glycol can be used.

The hard segment and the soft segment may be formed by, for example, a two step reaction of an oligomerization reaction and a polycondensation reaction. An oligomer is prepared by mixing a branching agent and a catalyst together with an aromatic dicarboxylic acid, a lower diol, and a polyalkylene oxide, and then reacting at 180 to 210 ° C. for 3 to 4 hours (the oligomerization step), followed by 210 to 250 ° C. A branched elastomer can be prepared by reacting under high vacuum for 4 to 5 hours at (polycondensation reaction step). The intrinsic viscosity of the polyester-based elastomer resin thus prepared may be 1.3 to 2.2 dl / g in the measurement using a solvent having a phenol (Phenol) / tetrachloroethane (TCE) of 50/50.

In the thermoplastic elastomer resin composition, the content of the polyester-based elastomer resin may be 67 to 96.7% by weight. If the content is less than 67% by weight, the tensile elongation may be lowered. If the content is more than 96.7% by weight, the adhesiveness may not be improved, and thus the moldability may not be improved.

Styrenic resin

Styrene-based resin according to embodiments of the present invention, for example, styrene-butadiene-styrene (SBS) block copolymer, styrene- ethylene- butylene- styrene block copolymer (Styrene -Ethylene-Butylene-Styrene (SEBS) Block Copolymer), Styrene-Isoprene-Styrene (SIS) Block Copolymer), Styrene-Butadiene Rubber (SBR), etc. It is possible to, but is not limited to.

The styrene resin may reduce the adhesiveness of the thermoplastic elastomer resin. Generally, polyester elastomer resins have low melting points and are incompatible with other resins, but have good compatibility with styrene rubbers, thereby maintaining their original properties and having uniform surface properties.

In the thermoplastic elastomer resin composition, the content of the styrene resin may be 3 to 30% by weight. If the content is less than 3% by weight can not improve the adhesion can not be obtained the desired moldability, if the content is more than 30% by weight due to the excessive use of the tensile elongation may be reduced to maintain the properties of the polyester-based elastomer.

Reactive additive

The reactive additive according to embodiments of the present invention may include a compound having a functional group of an isocyanate group, a carbodiimide group, or an epoxy group, but is not limited thereto. The compound may have the functional group at the terminal.

As an additive having the isocyanate group as a terminal functional group, hexamethylene diisocyanate (HDI), trans-cyclohexane 1,4-diisocyanate (CHDI), isoprene diisocyanate ( isophorone diisocyanate (IPDI), p-phenylene diisocyanate (PPDI), toluene 2,4-diisocyanate (TDI), naphthalene 1,5-diisocyanate (naphthalene 1, 5-diisocyanate (NDI), polymethylene polyphenylene polyisocyanate (Polymeric MDI), diphenylmethane 4,4'-diisocyanate (4-4 'MDI), di Phenylmethane 2,2'-diisocyanate (diphenylmethane 2,2'-diisocyanate, 2-2 'MDI) and the like can be used.

As an additive having a carbodiimide as a functional group, a compound having a structure of Formula 1 may be used. The compound of Formula 1 may be prepared by removing carbon dioxide using polyisocyanate or diisocyanate as starting material.

[Formula 1]

In Formula 1, R ₁ and R ₂ may each independently represent a hydrogen atom, an alkyl group, or an aryl group.

The compound of Formula 1 may be prepared by removing carbon dioxide using polyisocyanate or diisocyanate as starting material.

The diisocyanate is for example OCN-R-NCO, wherein R is an aliphatic hydrocarbon radical having 4 to 12 carbon atoms, an alicyclic or aromatic hydrocarbon radical having 6 to 15 carbon atoms, or 7 to 15 Aromatic aliphatic hydrocarbon radicals having 2 carbon atoms and the like. For example, hexamethylene diisocyanate (HDI), trans-cyclohexane 1,4-diisocyanate (CHDI), isoprene diisocyanate (IPDI), p- Phenylene diisocyanate (PPDI), toluene 2,4-diisocyanate (TDI), naphthalene 1,5-diisocyanate (NDI), poly Methylene polyphenylene polyisocyanate (Polymeric MDI), diphenylmethane 4,4'-diisocyanate (4-4 'MDI), diphenylmethane 2,2'-di Carbodiimides prepared using isocyanates (diphenylmethane 2,2'-diisocyanate, 2-2 'MDI) and the like may be used alone or in combination.

As the additive having an epoxy terminal functional group, an oxide compound such as ethylene oxide or propylene oxide may be used alone, or a compound having three or more epoxy terminals while having a styrene or acrylic backbone may be used. Can be used. For example, a polyoxide of Formula 2 or a styrene-acrylic oxide of Formula 3 may be used.

[Formula 2]

In Formula 2, n represents an integer of 1 to 15.

(3)

In Formula 3, R ₁ to R ₅ may each independently represent a hydrogen atom or an alkyl group, R ₆ may represent an alkyl group, and x, y, z may each independently represent an integer of 1 to 20. .

The reactive additive increases the molecular weight or partially crosslinks to increase the melt tension without impairing the properties such as recycling, which is an advantage of thermoplastics, thereby enabling blow molding. In addition, due to the increase in molecular weight, the adhesiveness is reduced to prevent molding defects.

In the thermoplastic resin composition, the content of the reactive additive may be 0.3 to 3.0% by weight. If the content is less than 0.3% by weight can not increase the melt tension significantly, the surface adhesion can not be significantly lowered to obtain the desired formability, if the content is more than 3.0% by weight can be reduced due to the excess reaction, the thermoplastic Properties may be lost and recycling may be difficult.

The thermoplastic elastomer resin composition may include one or more selected from antioxidants, light stabilizers, lubricants, reinforcing agents, and pigments according to desired properties.

In the method of preparing the thermoplastic elastomer resin composition, the polyester-based elastomer resin and the styrene-based resin are mixed, melted and kneaded using a twin screw extruder at a high temperature, and the reactive additive is added to the twin screw extruder to react during extrusion. Advancing, and cooling the melt from the extrusion die to produce a molding pellet.

In addition, the thermoplastic elastomer resin composition may provide a molded article by performing a blow process. Such molded articles may include various industrial materials and parts thereof, parts such as automobile air intake devices, exhaust devices and hoses.

Example

The raw materials were mixed with the ingredients and contents shown in Table 1 below, and the polyester elastomer resin and the styrene resin were melted and kneaded using a twin screw extruder at a temperature of 200 to 240 ° C., and the reaction extrusion was carried out using a reactive additive. It was. Molding pellets were prepared by cooling the melt from the extrusion die. The prepared pellets were hot-air dried at a temperature of 90 to 100 ° C. for at least 4 hours, and then injection molded at a temperature of 200 to 220 ° C. to prepare specimens.

Ingredient (content) Example 1 Example 2 Example 3 Example 4 Polyester elastomer resin (% by weight) 96.7 69.7 94.0 67 Styrene-based resin (% by weight) 3 30 3.0 30 Reactive Additives (wt%) 0.3 0.3 3.0 3.0

* Polyester elastomer resin: TRIEL 5550NA of Samyang Co., Ltd.-Shore hardness D 55

* Styrene resin: G1651H (styrene-ethylene-butadiene-styrene resin) from Kraton polymer

* Isocyanate: para-phenylene diisocyanate from Dupont

Comparative example

The raw materials were mixed with the ingredients and contents shown in Table 2 below, and the polyester elastomer resin and the styrene resin were melted and kneaded using a twin screw extruder at a temperature of 200 to 240 ° C., and the reaction extrusion was carried out using a reactive additive. It was. Molding pellets were prepared by cooling the melt from the extrusion die. The prepared pellets were hot-air dried at a temperature of 90 to 100 ° C. for at least 4 hours, and then injection molded at a temperature of 200 to 220 ° C. to prepare specimens.

Ingredient (content) Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 Polyester elastomer resin (% by weight) 100 98 99.8 95.0 65 60 Styrene-based resin (% by weight) 2.0 35 35 Reactive Additives (wt%) 0.2 5.0 5.0

* Polyester elastomer resin: TRIEL 5550NA of Samyang Co., Ltd.-Shore hardness D 55

* Styrene resin: G1651H (styrene-ethylene-butadiene-styrene resin) from Kraton polymer

* Isocyanate: para-phenylene diisocyanate from Dupont,

For the thermoplastic elastomer resin compositions prepared according to the above Examples and Comparative Examples, tensile elongation, tensile strength, adhesion and formability were measured by the following method, and the results are shown in Table 3 below.

(a) Tensile elongation: measured by ASTM D638.

(b) Tensile strength: measured by ASTM D638.

(c) Adhesiveness: Measured from the operator's perspective. ◎ is not attached at all, ○ is slightly attached, Δ is attached, but can be used.

(d) Formability: Measured from the operator's perspective. ◎ is very good, ○ is good, Δ is sagging, but moldable, X is sag, which means that it is impossible to mold or cannot be formed due to mechanical overload.

division Example Comparative example One 2 3 4 One 2 3 4 5 6 Tensile Elongation (%) 790 850 780 530 900 880 900 700 420 390 Tensile strength (kgf / ㎠) 245 205 260 160 250 230 260 275 125 150 Stickiness ○ ○ ○ ◎ X Δ X X ○ ○ Formability ○ Δ ◎ ◎ X X X X X X

As shown in Table 3, the thermoplastic elastomer resin composition prepared according to Examples 1 to 4 of the present invention is reduced, while maintaining the tensile elongation and tensile strength, compared to the thermoplastic elastomer resin composition prepared according to Comparative Examples 1 to 6 It can be seen that it can have a high adhesiveness and excellent moldability.

In Comparative Examples 1 to 5, when the amount of the styrene-based resin is less than 3% or when the reactive additive is less than 0.3%, sagging occurs due to lack of melt tension, and moldability is poor. In Comparative Examples 4 and 6, If the additive was more than 3.0%, the molding itself could not proceed with the mechanical load. In Comparative Examples 5 and 6, when the styrene-based resin was more than 30%, the tensile elongation and tensile strength did not meet the standard. In Comparative Examples 1, 3, and 4, when the styrene-based resin was not used, the adhesiveness did not decrease, and there was a phenomenon of sticking, resulting in molding failure.

Hereinafter, specific embodiments of the present invention have been described. It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. Therefore, the disclosed embodiments should be considered in an illustrative rather than a restrictive sense. The scope of the present invention is defined by the appended claims rather than by the foregoing description, and all differences within the scope of equivalents thereof should be construed as being included in the present invention.

Claims (9)

67-96.7 wt% polyester elastomer resin; 3 to 30% by weight of styrene resin; And A thermoplastic elastomer resin composition comprising 0.3 to 3.0% by weight reactive additive, The polyester-based elastomer resin is composed of a hard segment and a soft segment of polyalkylene oxide prepared by polymerizing at least one selected from aromatic dicarboxylic acid and aromatic dicarboxylate and a lower diol, The aromatic dicarboxylic acids include terephthalic acid (TPA), isophthalic acid (IPA), 1,5-naphthalene dicarboxylic acid (1,5-NDCA), and 2,6-naphthalene dicarboxylic acid (2,6-NDCA At least one selected from the group consisting of, wherein the aromatic dicarboxylate is dimethyl isophthalate (Dimethyl Isophthalate), the lower diol is ethylene glycol, propylene glycol, 1,4-butanediol, 1,5-pentanediol , 1,6-hexanediol and 1,4-cyclohexanedimethanol, the polyalkylene oxide being selected from the group consisting of polyoxyethylene glyoxypropylene glycol and polyoxytetramethylene glycol At least one selected; The styrene-based polymer is a styrene-butadiene-styrene block copolymer, a styrene-butylene-styrene block copolymer, a styrene-butyene-styrene block copolymer ), Styrene-isoprene-styrene block (Styrene-Styrene (SIS) Block Copolymer), and styrene-butadiene rubber (Styrene-Butadiene Rubber, SBR); The reactive additive is a thermoplastic elastomer resin composition comprising at least one selected from the group consisting of compounds having functional groups of isocyanate group, carbodiimide group, or epoxy group. delete delete delete delete delete delete The method of claim 1, At least one of the compounds having a functional group of an isocyanate group, a carbodiimide group, or an epoxy group has the functional group at the terminal, characterized in that the thermoplastic elastomer resin composition. The method of claim 1, A thermoplastic elastomer resin composition further comprising at least one selected from the group consisting of antioxidants, light stabilizers, lubricants, reinforcing agents and pigments.