KR20160139451A - Polyketone film having excellent barrier property - Google Patents

Abstract

The present invention relates to a polyketone film having excellent barrier characteristics and, more particularly, to a polyketone film using a dope solution dissolving a ketone copolymer in an aqueous metal salt solution. The polyketone film has excellent strength and barrier characteristics. Also, the ketone copolymer includes repeat units represented by chemical formulae 1 and 2, -[-CH_2CH_2-CO-]_x-, and -[-CH_2CH(CH_3)-CO-]_y-, wherein y/x is 0-0.1. The weight distribution of the ketone copolymer is 2.5-3.5.

Description

POLYKETONE FILM HAVING EXCELLENT BARRIER PROPERTY "

The present invention relates to a polyketone film having excellent barrier properties, and more particularly, to a polyketone film having excellent barrier properties, and more particularly, to a polyketone film having excellent barrier properties, And to an excellent polyketone film.

In order to store foods or medicines for a long period of time, it is necessary to carry out packaging excellent in gas barrier property which has the effect of blocking the penetration of oxygen or water vapor from outside air that promotes corruption and deterioration. The film having excellent gas barrier properties also requires transparency.

As a method for imparting gas barrier property, a method of attaching an aluminum foil to a polyester film, a method of depositing a metal such as aluminum on a polyester film, or the like is used. However, although these methods have excellent gas barrier properties, the obtained film is opaque and has the disadvantage that the contents to be packed are not visible

And its use is limited.

As another method, a transparent film having a gas barrier property such as a polyvinylidene chloride film, a polyethylene polyvinyl alcohol copolymer film and the like may be adhered to a polyester film Method is used. However, these films have a drawback of being excellent in transparency but lacking in heat resistance, and having reduced gas barrier properties due to high temperature treatment such as retort treatment.

As a method for imparting gas barrier properties which are transparent and heat-resistant, there is known a method of depositing an oxide such as silicon oxide or aluminum oxide on a polyester film to form a transparent thin film.

There is also a method of co-extruding a polyester resin and another resin to impart gas barrier properties.

However, a method of depositing an inorganic material or the like on a polyester resin, a method of laminating another film to a polyester film, and a method of co-extruding a polyester resin and another resin have disadvantages in that the production cost increases and the product yield decreases.

It is an object of the present invention to provide a polyketone film having not only excellent strength but also excellent barrier properties.

In order to achieve the above object, the present invention provides a polyketone copolymer comprising a repeating unit represented by the following general formulas (1) and (2) and having a molecular weight distribution of 2.5 to 3.5 and y / Is dissolved in a metal salt aqueous solution to prepare a dope solution and applied on a support, followed by stretching, wherein the polyketone film has a longitudinal direction (MD) strength of 100 MPa or more and a crystallinity of 25% or less, A polyketone film excellent in barrier properties is provided, which has an air permeability and a moisture permeability of 50 cc / m 2 · day · atm or less and 20 cc / m 2 · day · atm or less, respectively.

At this time, the ligand of the catalyst composition used in the polymerization of the polyketone copolymer is a mixture of ((2,2-dimethyl-1,3-dioxane-5,5-diyl) bis (methylene) And the intrinsic viscosity of the polyketone copolymer is 5.0 to 7.0, and the metal salt aqueous solution is composed of ZnCl2 / CaCl2, ZnCl2 / LiCL, ZnCl2 / CaSCN, ZnCl2 / CaCl2 / LiCl and ZnCl2 / Cacl2 / CaSCN Is an aqueous solution of a metal salt.

The micropore of the polyketone film preferably has an average diameter of 0.1 to 10 占 퐉.

The polyketone film according to the present invention has an air permeability and a water vapor permeability of 50 cc / m 2 · day · atm or less and 20 cc / m 2 · day · atm or less, respectively. Accordingly, the polyketone film has excellent barrier properties and is suitable for food packaging or industrial use.

Hereinafter, the present invention will be described.

The present invention relates to a process for preparing a dope solution by dissolving a polyketone copolymer composed of the repeating units represented by the following general formulas (1) and (2) and having a molecular weight distribution of 2.5 to 3.5 and y / (MD) strength of 100 MPa or more, a degree of crystallinity of 25% or less, a degree of permeability and a moisture permeability of 50 cc / m < 2 > day · atm or less and 20 cc / m 2 · day · atm or less.

First, the polymerization method of the polyketone used in the present invention will be described in detail.

One or more olefinically unsaturated compounds (simply referred to as " A "), wherein the monomer units are alternating, and thus the polymer is composed of units of the formula - (CO) -A'- wherein A 'represents the monomer units derived from the applied monomer A ) And a high molecular weight linear polymer of carbon monoxide can be prepared by contacting the monomer with a solution of the palladium-containing catalyst composition in a dilute solution in which the polymer does not dissolve or actually dissolve. During the polymerization process, the polymer is obtained in the form of a suspension in a diluent. The polymer preparation is carried out primarily batchwise.

The batchwise preparation of the polymer is typically carried out by introducing the catalyst into a reactor containing the diluent and the monomer and having the desired temperature and pressure. As the polymerization proceeds, the pressure drops, the concentration of the polymer in the diluent increases, and the viscosity of the suspension increases. The polymerization is continued until the viscosity of the suspension reaches a high value, for example, to the point where difficulties associated with heat removal occur. During batch polymer preparation, monomers can be added to the reactor during polymerization, if desired, to maintain the temperature as well as the pressure constant.

In the present invention, not only methanol, dichloromethane or nitromethane, which has been conventionally used for producing polyketones, but also mixed solvents comprising acetic acid and water, ethanol, propanol, and isopropanol can be used as the liquid medium. Particularly, when a mixed solvent of acetic acid and water is used as a liquid medium in the production of polyketone, the catalyst activity can be improved while reducing the production cost of polyketone. Further, since the use of methanol or a dichloromethane solvent forms a mechanism for causing a stopping reaction during the polymerization step, the use of acetic acid or water other than methanol or dichloromethane in the solvent does not have an effect of stopping the catalytic activity stochastically, It plays a big role in improvement.

When a mixed solvent of acetic acid and water is used as a liquid medium, when the concentration of water is less than 10% by volume, the activity is less affected by the catalytic activity, but when the concentration is 10% by volume or more, the catalytic activity increases sharply. On the other hand, when the concentration of water exceeds 30% by volume, the catalytic activity tends to decrease. In the present invention, it is preferable to use a mixed solvent comprising 70 to 90% by volume of acetic acid and 30 to 10% by volume of water as the liquid medium.

In the present invention, the organometallic complex catalyst comprises (a) a Group 9, Group 10 or Group 11 transition metal compound of the Periodic Table of the Elements (IUPAC Inorganic Chemical Nomenclature Revised Edition, 1989), (b) And (c) an anion of an acid having a pKa of 4 or less.

Examples of the Group 9 transition metal compound in the ninth, tenth, or eleventh group transition metal compound (a) include complexes of cobalt or ruthenium, carbonates, phosphates, carbamates, and sulfonates, Specific examples thereof include cobalt acetate, cobalt acetylacetate, ruthenium acetate, ruthenium trifluoroacetate, ruthenium acetylacetate and ruthenium trifluoromethanesulfonate.

Examples of the Group 10 transition metal compounds include complexes of nickel or palladium, carbonates, phosphates, carbamates, and sulfonates. Specific examples thereof include nickel acetate, nickel acetyl acetate, palladium acetate, palladium trifluoroacetate , Palladium acetylacetate, palladium chloride, bis (N, N-diethylcarbamate) bis (diethylamine) palladium and palladium sulfate.

Examples of the Group 11 transition metal compound include a complex of copper and silver, a carbonate, a phosphate, a carbamate, and a sulfonate, and specific examples thereof include copper acetate, copper trifluoroacetate, copper acetylacetate, Examples of the trifluoroacetic acid include silver acetyl acetate, trifluoromethanesulfonic acid and the like.

Of these, transition metal compounds (a), which are inexpensive and economically preferable, are nickel and copper compounds, and preferable transition metal compounds (a) in terms of yield and molecular weight of polyketones are palladium compounds, It is most preferable to use palladium acetate.

Examples of ligands (b) having a Group 15 atom include 2,2-bipyridyl, 4,4-dimethyl-2,2-bipyridyl, 2,2- (Diphenylphosphino) propane, 1,4-bis (diphenylphosphino) butane, 1,3-bis (diphenylphosphino) Bis [di (2-methylphenyl) phosphino] propane, 1,3-bis [di (2-isopropyl) Bis (diphenylphosphino) cyclohexane, 1,2-bis (diphenylphosphino) phosphine, ) Benzene, 1,2-bis [(diphenylphosphino) methyl] benzene, 1,2-bis [[di (2-methoxyphenyl) Bis (diphenylphosphino) ferrocene, 2-hydroxy-1,3-bis [di (2-methoxyphenyl) ) Phosphino] propane, 2,2-dimethyl-1,3-bis [di (2-methoxyphenyl) Phosphino] propane, and the like.

Among these ligands, preferred ligands (b) having a Group 15 element are phosphorus ligands having an atom of Group 15, and particularly preferred ligands in terms of yield of polyketone are 1,3-bis [di (2- Methoxyphenyl) phosphino] propane and 1,2-bis [[di (2-methoxyphenyl) phosphino] methyl] benzene, Di (2-methoxyphenyl) phosphino] propane, and it is safe in that it does not require an organic solvent. Soluble sodium salts such as 1,3-bis [di (2-methoxy-4-sulfonic acid sodium-phenyl) phosphino] propane, 1,2- ] Methyl] benzene, and 1,3-bis (diphenylphosphino) propane and 1,4-bis (diphenylphosphino) butane are preferred for ease of synthesis and availability in large quantities and economically.

The ligand (b) having a group 15 atom preferred in the present invention, which focuses on the intrinsic viscosity and catalytic activity of the polyketone, is 1,3-bis- [di (2-methoxyphenyl) Bis (bis (methylene)) bis (bis (2-methoxyphenyl) phosphine), and more preferably 1,3-bis Bis (methylene)) bis (bis (2-methoxyphenyl) phosphino] propane or ((2,2-dimethyl-1,3-dioxane-5,5- ) Phosphine) is better.

[Chemical Formula 1]

.

.

      Bis (bis (2-methoxyphenyl) phosphine) bis ((2,2-dimethyl-1,3-dioxane-5,5-diyl) bis Activity equivalent to that of 3,3-bis- [bis- (2-methoxyphenyl) phosphanylmethyl] -1,5-dioxa-spiro [5,5] undecane, which is known to exhibit the highest activity among polymerization catalysts The structure is simpler and has a lower molecular weight. As a result, the present invention has been able to provide a novel polyketone polymerization catalyst having the highest activity as a polyketone polymerization catalyst of the present invention, while further reducing its manufacturing cost and cost. A method for producing a ligand for a polyketone polymerization catalyst is as follows. ((2,2-dimethyl) -2,3-dioxolane was obtained by using bis (2-methoxyphenyl) phosphine, 5,5-bis (bromomethyl) Bis (bis (methylene)) bis (bis (2-methoxyphenyl) phosphine) is obtained by reacting a bis (methylene) . The process for preparing a ligand for a polyketone polymerization catalyst according to the present invention is a process for producing a ligand for a polyketone polymerization catalyst which comprises reacting 3,3-bis- [bis- (2-methoxyphenyl) phosphanylmethyl] -1,5-dioxa-spiro [5,5] ((2,2-dimethyl-1,3-dioxane-5,5-diyl) bis (methylene)) bis (bis (2- Methoxyphenyl) phosphine) can be commercially synthesized in a large amount.

  In a preferred embodiment, the process for preparing a ligand for a polyketone polymerization catalyst of the present invention comprises: (a) introducing bis (2-methoxyphenyl) phosphine and dimethylsulfoxide (DMSO) into a reaction vessel under nitrogen atmosphere, Adding sodium and stirring; (b) adding 5,5-bis (bromomethyl) -2,2-dimethyl-1,3-dioxane and dimethylsulfoxide to the resulting mixture, followed by stirring and reacting; (c) adding methanol and stirring after completion of the reaction; (d) adding toluene and water, separating the layers, washing the oil layer with water, drying with anhydrous sodium sulfate, filtering under reduced pressure, and concentrating under reduced pressure; And (e) the residue was recrystallized from methanol to obtain ((2,2-dimethyl-1,3-dioxane-5,5- diyl) bis (methylene)) bis (bis (2- methoxyphenyl) And a step of acquiring the image data.

The amount of the Group 9, Group 10 or Group 11 transition metal compound (a) varies depending on the kind of the ethylenically unsaturated compound to be selected and other polymerization conditions. But is usually 0.01 to 100 mmol, preferably 0.01 to 10 mmol, per liter of the reaction volume of the reaction zone. The capacity of the reaction zone means the liquid phase capacity of the reactor.

Examples of the anion (c) of the acid having a pKa of 4 or less include an anion of an organic acid having a pKa of 4 or less, such as trifluoroacetic acid, trifluoromethanesulfonic acid, p-toluenesulfonic acid, or m-toluenesulfonic acid; Anions of inorganic acids having a pKa of 4 or less such as perchloric acid, sulfuric acid, nitric acid, phosphoric acid, heteropoly acid, tetrafluoroboric acid, hexafluorophosphoric acid, and fluorosilicic acid; And anions of boron compounds such as trispentafluorophenylborane, trisphenylcarbenium tetrakis (pentafluorophenyl) borate, and N, N-dimethylarinium tetrakis (pentafluorophenyl) borate.

Particularly, the anion (c) of the acid having a pKa of 4 or less, which is preferable in the present invention, is p-toluenesulfonic acid, which has high catalytic activity when used with a mixed solvent of acetic acid and water as a liquid medium, It becomes possible to produce a polyketone having a high intrinsic viscosity suitable for the polyolefin.

The molar ratio of (a) the ninth, tenth or eleventh group transition metal compound and (b) the ligand having an element of Group 15 element is 0.1 to 20 moles of the Group 15 element of the ligand per 1 mole of the palladium element, Is preferably added in a proportion of 0.1 to 10 moles, more preferably 0.1 to 5 moles. When the ligand is added in an amount of less than 0.1 mole based on the palladium element, the binding force between the ligand and the transition metal decreases, accelerating the desorption of the palladium during the reaction, and causing the reaction to terminate quickly. When the ligand exceeds 20 moles When added, the ligand is shielded from the polymerization reaction by the organometallic complex catalyst, so that the reaction rate is remarkably lowered.

The molar ratio of (a) the anion of the ninth, tenth or eleventh group transition metal compound and (c) the anion of the acid having a pKa of 4 or less is 0.1 to 20 mol, preferably 0.1 to 10 mol, Mol, and more preferably 0.1 to 5 mol. When the acid is added in an amount of less than 0.1 mol based on the palladium element, the effect of improving the intrinsic viscosity of the polyketone is unsatisfactory. If the acid is added in an amount exceeding 20 mol based on the palladium element, the catalytic activity for producing the polyketone tends to be rather reduced. not.

In the present invention, the reaction gas to be reacted with the catalyst for producing polyketone is preferably a mixture of carbon monoxide and an ethylenically unsaturated compound.

Examples of the ethylenically unsaturated compound copolymerized with carbon monoxide include ethylene, propylene, 1-butene, 1-hexene, 4-methyl-1-pentene, 1-octene, C2-C20 alpha-olefins including hexadecene, vinylcyclohexane; Styrene, C2-C20 alkenyl aromatic compounds including? -Methylstyrene; But are not limited to, cyclopentene, norbornene, 5-methylnorbornene, 5-phenylnorbornene, tetracyclododecene, tricyclododecene, tricyclodecene, pentacyclopentadecene, pentacyclohexadecene, C4 to C40 cyclic olefins including cyclododecene; C2 to C10 halogenated vinyls containing vinyl chloride; Ethyl acrylate, methyl acrylate, and mixtures of two or more selected from among C3 to C30 acrylic esters. These ethylenically unsaturated compounds are used singly or as a mixture of plural kinds. Of these, preferred ethylenically unsaturated compounds are? -Olefins, more preferably? -Olefins having 2 to 4 carbon atoms, and most preferably ethylene.

In the production of polyketones, the charging ratio of the carbon monoxide and the ethylenic unsaturated compound is generally 1: 1. In the present invention, the charging ratio of the carbon monoxide and the ethylenic unsaturated compound is adjusted to a molar ratio of 1:10 to 10: 1 . As in the present invention, when an ethylenically unsaturated compound and carbon monoxide are mixed in an appropriate ratio, they are effective also in terms of catalytic activity, and the intrinsic viscosity improvement effect of the produced polyketone can be simultaneously achieved. When carbon monoxide or ethylene is added in an amount of less than 5 mol% or more than 95 mol%, the reactivity is poor and the physical properties of the produced polyketone may be deteriorated.

The polyketone polymer preferably used in the present invention is a copolymer of carbon monoxide and ethene or a second ethylenically unsaturated hydrocarbon having carbon monoxide, ethene and at least three carbon atoms, in particular alpha-olefins such as propene Is a terpolymer.

When the polyketone terpolymer is used as the main polymer component of the blend of the present invention, there are at least two units containing an ethylene moiety in each unit containing the second hydrocarbon moiety in the terpolymer. It is preferable that the number of units containing the second hydrocarbon moiety is from 10 to 100.

In one embodiment, the polyketone polymer is a copolymer comprising repeating units represented by the general formulas (1) and (2), and it is preferable that y / x is 0.01 or less. When the value of the y / x value exceeds 0.01, the mechanical properties are deteriorated.

- [- CH2CH2-CO] x- (1)

- [- CH2 --CH (CH3) - CO] y - (2)

On the other hand, the total melting point of the polymer used in the present invention is 175 ° C to 300 ° C, and generally 210 ° C to 270 ° C. The intrinsic viscosity (LVN) of the polymer measured by HFIP (Hexafluoroisopropylalcohol) at 60 DEG C using a standard tubular viscosity measuring apparatus is 0.5 dl / g to 10 dl / g, and preferably 5.0 dl / g to 7.0 dl / g . At this time, when the intrinsic viscosity of the polyketone polymer is less than 5.0, the mechanical strength (abrasion resistance) during production into a porous body is lowered.

A preferred process for producing a polyketone polymer is disclosed in U.S. Patent No. 4,843,144. In the present invention, a mixed solvent of acetic acid and water is used as a liquid medium, and the polymerization reaction is caused by a catalyst composition composed of (a) a palladium compound, (b) a bidentate ligand and (c) an anion of an acid having a pKa of 4 or less , The catalyst is produced by contacting the three components. Any method may be employed. A solution prepared by preliminarily mixing three components in a suitable solvent may be used, or the three components may be supplied to the polymerization system and contacted in the polymerization system.

On the other hand, it is preferable that the molecular weight distribution of the polyketone is 2.5 to 3.5, and if it is less than 2.5, the polymerization yield is lowered. In order to control the molecular weight distribution, it is possible to adjust proportionally according to the amount of the palladium catalyst and the polymerization temperature. That is, when the amount of the palladium catalyst is increased or when the polymerization temperature is 100 ° C or higher, the molecular weight distribution becomes larger.

In carrying out the present invention, the polymerization method includes a solution polymerization method using a liquid medium, a suspension polymerization method, a vapor phase polymerization method in which a small amount of a polymer is impregnated with a high concentration catalyst solution, and the like. The polymerization may be either batchwise or continuous. The reactor used in the polymerization can be used as it is or in a known manner. The polymerization temperature is not particularly limited and generally 40 to 250 占 폚, preferably 50 to 180 占 폚 is employed. If the reaction temperature is less than 40 ° C, the polymerization reaction is poor and the reaction does not proceed. If the reaction temperature exceeds 250 ° C, a side reaction such as oligomerization or monomer preparation and decomposition reaction is more active than polymerization reaction with a polymer, . The pressure at the time of polymerization is not particularly limited, but is generally from normal pressure to 20 MPa, preferably from 4 to 15 MPa. The polymerization reaction rate is very low at a pressure lower than the atmospheric pressure, and the side reaction speed is increased at a pressure of 20 MPa or higher.

Hereinafter, a method for preparing a dope by using the polyketone copolymer and producing a film will be described.

In the present invention, a dope solution prepared by dissolving three metal salts of ZnCl 2, CaCl 2, and LiCl in water as a solvent to prepare an aqueous metal salt solution and then dissolving the polyketone copolymer in the metal salt aqueous solution is used. Wherein the aqueous metal salt solution is an aqueous solution of a metal salt selected from the group consisting of ZnCl2 / CaCl2, ZnCl2 / LiCL, ZnCl2 / CaSCN, ZnCl2 / CaCl2 / LiCl and ZnCl2 / CaCl2 / CaSCN.

When the dope solution is prepared, the prepared dope solution is applied on the support to a constant thickness. The dope solution is applied to one side of the support uniformly as the support first passes from left to right and passes through a certain distance between the drum and the knife. According to various embodiments of the present invention, in addition to the knife and the drum, the means for applying the dope solution includes a knife and a glass plate, a plate or a drum made of a smooth material having a knife and a surface smoothly processed and a glass plate, a drum and a drum, Extruders and extruders, extruders and drums, extruders and plates of solid material whose surfaces have been smoothly worked.

The dope solution which can be used in the present invention is prepared by dissolving a metal salt consisting of three kinds of ZnCl 2, CaCl 2 and LiCl in water to prepare a metal salt aqueous solution and then dissolving the polyketone copolymer in a solvent in the metal salt aqueous solution. The total concentration of the three metal salts in the aqueous solution is preferably 60 to 70 wt%. If the content of the metal salt is less than 60 wt%, the polyketone copolymer may not be completely dissolved and the polymer remaining in the dope may become an impurity. If the content exceeds 70 wt%, the viscosity of the dope solution is low.

The content of the metal salt aqueous solution is preferably 60 to 70 wt% with respect to the total dope solution, and the content of the polyketone copolymer is preferably 2 to 10 wt% with respect to the total dope solution. If the content of the copolymer in the dope solution is less than 2 wt%, the physical properties of the porous body may be weakened. If the content of the copolymer exceeds 10 wt%, the solution viscosity is too large to be coated and the porosity becomes small.

Meanwhile, a porosity regulator may be added to the dope solution to control the pore size of the separation membrane. Examples of the pore regulator include poly (ethylene glycol), poly (vinylpyrrolidone), poly (vinyl alcohol), and the like having various molecular weights. In order to reduce pore size, 1,4-dioxane, diethylene glycol dimethyl Ether and the like can be selected and used.

When the dope solution is prepared, the prepared dope solution is applied on the support to a constant thickness. The dope solution is applied to one side of the support uniformly as the support first passes from left to right and passes through a certain distance between the drum and the knife. Here, as a means for applying the coating solution, a plate or a drum, a glass plate, a drum and a drum, and a hard material whose surface is smoothly processed, such as a knife and a glass plate, a knife and a smooth surface, Plate or extruder, a glass plate, an extruder, a drum, an extruder, and a plate made of a hard material having a smooth surface.

The support on which the dope solution has been applied is impregnated with water or 1 to 10 wt% of a metal salt aqueous solution at 2 to 80 ° C to undergo a phase transition process to prepare a porous article. The solidification process is preferably performed in a temperature range of -10 to 100 캜, more preferably in a temperature range of 1 to 60 캜.

After the solidification process, the prepared porous body may be washed three times with HCl aqueous solution of 0.05% at 60 ° C and then washed with distilled water to remove the metal salt.

An unoriented polyketone film is produced through the above process.

Thereafter, the polyketone film having excellent barrier properties can be produced by stretching the unstretched polyketone film.

Here, the polyketone film is characterized in that the strength in the longitudinal direction (MD) is 100 MPa or more, the crystallinity is 25% or less, the permeability and the moisture permeability are respectively 50 cc / m 2 · day · atm and 20 cc / m 2 · day · atm . The micropore of the polyketone film has an average diameter of 0.1 to 10 mu m.

Hereinafter, the present invention will be described in detail with reference to specific examples. The embodiments shown are merely illustrative of the present invention and are not intended to limit the scope of the present invention.

Example  One

The linear alternating polyketone copolymer composed of carbon monoxide and ethylene is prepared by reacting palladium acetate, trifluoroacetic acid and ((2,2-dimethyl-1,3-dioxane-5,5-diyl) bis (methylene) -Methoxyphenyl) phosphine). ≪ / RTI > In the above, the content of trifluoroacetic acid relative to palladium is 7 times the molar ratio and is subjected to two steps of 1 stage of polymerization temperature 72 ° C and 84 ° C. The polyketone copolymer prepared above had a melting point of 225 ° C, an LVN of 6.2 dl / g measured by HFIP (hexa-fluoroisopropano) at 25 ° C, and an MWD of 3.0.

The polyketone copolymer was added to a 62 wt% metal salt aqueous solution having a concentration of 8 wt% ZnCl 2 / CaCl 2 / LiCl = 22: 30: 10 wt%, the polyketone doped solution was sealed under reduced pressure, Followed by decompression at 70 DEG C and 750 mmHg for 30 minutes to remove air bubbles to form a transparent polyketone doped solution.

The polyketone doped solution was filtered with a filter to remove impurities, and then cast through a Ti-die. At this time, the slit T-die temperature was maintained at 60 to 70 DEG C, the distance between the tee-die and the casting drum was 30 mu m, the coagulation bath temperature and the drum temperature were maintained at 3 DEG C, Was maintained at 2 m / min.

The cast polyketone gel film was passed through an air gap having a length of 10 mm and immersed for 90 seconds in a coagulation bath containing a coagulating solution composed of water at 4 캜 for solidification. The polyketone film was transferred to a cleaning bath containing a hydrochloric acid solution and washed to prepare an unoriented polyketone film.

Thereafter, the unstretched polyketone film was stretched under the conditions of a stretching temperature of 220 deg. C, an elongation of 2 times (MD direction) and a stretching speed of 75 mm / min.

Example  2

A polyketone film was produced in the same manner as in Example 1, except that the unstretched polyketone film was stretched under the conditions of an elongation of 2 times (MD direction) and an elongation of 3 times (MD direction).

Example  3

A polyketone film was produced in the same manner as in Example 1 except that the unstretched polyketone film was stretched under the conditions of an elongation of 2 times (MD direction) and an elongation of 4 times (MD direction).

Comparative Example  One

A polyketone film was prepared in the same manner as in Example 1, except that the stretching was not performed.

Comparative Example  2

The polypropylene dope solution was filtered through a filter to remove impurities and then cast through a Ti-die. At this time, the slit T-die temperature was maintained at 60 to 70 DEG C, the distance between the tee-die and the casting drum was 30 mu m, the coagulation bath temperature and the drum temperature were maintained at 3 DEG C, Was maintained at 2 m / min.

The cast polypropylene gel film was passed through an air gap having a length of 10 mm and immersed for 90 seconds in a coagulation bath containing a coagulating solution composed of water at 4 캜 for solidification. The polypropylene film was transferred to a cleaning bath containing a hydrochloric acid solution and washed to prepare a polypropylene film.

Property evaluation

The physical properties of the polyketone films prepared in Examples 1 to 3 and Comparative Example 1 were measured by the following methods, and the results are shown in Table 1 below.

(1) Heat shrinkage

The film was cut in a normal direction of 9 m × 9 m to measure the length in the longitudinal direction (MD) of the film. The film was heat-shrunk in an oven at 150 ° C. for 30 minutes in an unloaded state, MD) was measured and the heat shrinkage ratio in the longitudinal direction (MD) was obtained according to the following formula.

Heat shrinkage percentage (%) = (length before shrinkage - length after shrinkage) / (length before shrinkage) x 100

(2) Oxygen permeability

The permeability (cc / m 2 · day · atm) of oxygen was measured using an air permeability meter (OX-TRAM 2/21, MOCON, USA) according to the standard measurement method of ASTM D3985.

(3) Water vapor permeability

The sample was placed in a moisture permeability meter (PERMATRAN-WTM Model 3/33) to measure moisture, measured at 38 ° C and 90% RH, and then expressed in terms of moisture permeability (g / m 2 · day · atm) .

Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Stretching condition Stretching (× 2) Stretching (× 3) Stretching (× 4) Unfinished Unfinished MD direction Strength (MPa) 75 87 105 - - Shinto (%) 1.40 1.54 1.43 - - CD direction Strength (MPa) 15 16 16 - - Shinto (%) 1.03 1.24 0.19 - - Crystallinity (%) 21.2 21.6 21.0 21.2 - Crystal orientation 0.761 0.851 0.900 0 - Heat shrinkage (%) 0 0 0 - 40 Oxygen permeability (cc / m 2 · day · atm) 49.7 43.5 35.2 68.5 67.2 Water vapor permeability (cc / ㎡ · day · atm) 22.4 19.5 15.7 27.3 26.7

Claims (5)

A dope solution is prepared by dissolving a polyketone copolymer composed of the repeating units represented by the following general formulas (1) and (2) and having a molecular weight distribution of 2.5 to 3.5 and y / x of 0 to 0.1 in a metal salt aqueous solution, (MD) strength of 100 MPa or more, a degree of crystallinity of 25% or less, an air permeability and a moisture permeability of 50 cc / m 2 · day · atm Or less and 20 cc / m 2 · day · atm or less.
- [- CH2CH2-CO-] x- (1)
- [- CH2 --CH (CH3) - CO--] y- (2)
(x and y are mole% of each of the general formulas (1) and (2) in the polymer) The method according to claim 1,
The ligand of the catalyst composition used in the polymerization of the polyketone copolymer is preferably selected from the group consisting of bis (2,2-dimethyl-1,3-dioxane-5,5-diyl) bis (methylene) ) ≪ / RTI > phosphine). The method according to claim 1,
Wherein the polyketone copolymer has an intrinsic viscosity of 5.0 to 7.0. The method according to claim 1,
Wherein the metal salt aqueous solution is an aqueous solution of a metal salt selected from the group consisting of ZnCl2 / CaCl2, ZnCl2 / LiCL, ZnCl2 / CaSCN, ZnCl2 / CaCl2 / LiCl and ZnCl2 / CaCl2 / CaSCN. The method according to claim 1,
Wherein the micropore of the polyketone film has an average diameter of 0.1 to 10 占 퐉.