KR19990007022A - Vinylidene chloride copolymer resin composition, film thereof and extrusion processing method - Google Patents

Abstract

Provided is a vinylidene chloride copolymer resin composition capable of producing a film having good extrusion processability in film production and excellent in performance, retortability and gas barrier properties. It consists of 50 mass% or more of vinylidene chloride copolymers (I) and 50 mass% or less of vinylidene chloride copolymers (II), and the reduced viscosity of a vinylidene chloride copolymer (I) exceeds 0.048-0.075, and a vinylidene chloride air Vinylidene chloride copolymer resin composition, characterized in that the reduced viscosity of the copolymer (II) is in the range of 0.048 to 0.060 and the reduced viscosity of the vinylidene chloride copolymer (I) is larger than the vinylidene chloride copolymer (II). And extruding the film and the resin composition made by the vacuum hopper mounting extruder.

Description

Vinylidene chloride copolymer resin composition, film thereof and extrusion processing method

The present invention relates to a resin composition containing a vinylidene chloride copolymer, an extrusion process thereof, and a film formed therefrom. More specifically, the present invention relates to a resin composition comprising at least two vinylidene chloride copolymers having different reducing viscosities, an extrusion process thereof, and a film formed therefrom. The resin composition is excellent in extrusion processability at the time of film production, and the film formed therefrom is excellent in seal aptitude, retort aptitude, and gas barrier property.

In general, vinylidene chloride copolymers have excellent properties of shielding of gases such as water vapor and oxygen, and are used in food packaging films and the like. However, the conventional vinylidene chloride copolymer itself has poor thermal stability and is easy to thermally decompose, so that extrusion processing becomes unstable, and it is difficult to obtain a packaging film utilizing its characteristics. Therefore, various improvement methods have been proposed conventionally.

However, as a method of improving the extrusion processability of vinylidene chloride copolymer, even by simply mixing conventional resins or additives, lowering other film properties required for films such as performance, retortability, and gas barrier properties, etc. There are many, and the vinylidene chloride-type resin which has these balanced characteristics in good balance is desired.

As a means for improving the extrudability of the vinylidene chloride copolymer resin, a method of suppressing heat generation during extrusion of the resin is employed. For example, it may be considered to reduce the degree of polymerization of the resin or to use a large amount of additives. However, if the polymerization degree of resin is made small, PVDC (abbreviation of vinylidene chloride copolymer) itself will embrittle, and performance and retort ability will fall. On the other hand, when the polymerization degree of resin is enlarged and a large amount of additive is used, gas barrier property will fall.

In addition, Japanese Patent Application Laid-Open No. 7-179703 discloses a vinylidene chloride copolymer resin composition A having a molecular weight of 50,000 to 300,000 and a molecular weight of 0.5 million. A composite vinylidene chloride copolymer resin composition made of a vinylidene chloride copolymer resin composition B of which phase is 0.8 times the weight average molecular weight of vinylidene chloride copolymer resin composition A or less than 80,000 (reduced viscosity is about 0.044). And a single layer film made from the composite vinylidene chloride copolymer resin composition. The resin composition is excellent in molding processability and the film is excellent in gas barrier property and the like. International Publication No. WO96-34050 discloses a mixed PVDC consisting of a PVDC having a reduced viscosity of at least 0.048 and a PVDC having a reducing viscosity of less than 0.048, and a PVDC-containing resin composition composed of 0.1 to 20 mass% of other copolymers. However, the performance or retort performance of the film needs further improvement.

This invention provides the vinylidene chloride copolymer resin composition which provides the film which is excellent in extrusion processability, and has performance, retort suitability, and gas barrier property, the extrusion process using the same, and the said film obtained from it.

The inventors of the present invention have shown that a vinylidene chloride copolymer resin composition obtained by mixing a vinylidene chloride copolymer having a different reducing viscosity at a specific ratio has excellent extrusion processability, and the film formed therefrom has excellent performance, retortability, and gas barrier properties. The inventors have found that the above characteristics can be further improved by using a vacuum hopper-mounted extruder when forming a film from the vinylidene chloride copolymer resin composition.

That is, the 1st of this invention consists of 50 mass% or more of vinylidene chloride copolymers (I) and 50 mass% or less of vinylidene chloride copolymers (II), and the reduced viscosity of a vinylidene chloride copolymer (I) is The reduced viscosity of the vinylidene chloride copolymer (I) is greater than 0.048 to 0.075 and the vinylidene chloride copolymer (II) is in the range of 0.048 to 0.060, and the reduced viscosity of the vinylidene chloride copolymer (I) is larger than that of the vinylidene chloride copolymer (II). It is to provide a vinylidene chloride copolymer resin composition.

A second aspect of the present invention is to provide an extrusion processing method, wherein the vinylidene chloride copolymer resin composition is extruded by a vacuum hopper mounting extruder.

Moreover, the 3rd of this invention provides the film which consists of the vinylidene chloride copolymer resin composition provided by the 1st of this invention.

Hereinafter, the first of the present invention will be described in detail.

Since the vinylidene chloride copolymer (I) and the vinylidene chloride copolymer (II) used by this invention are easy to obtain the copolymer which can be extruded, Preferably it is obtained by suspension polymerization, It is a copolymer with at least 1 ethylenically unsaturated monomer copolymerizable with vinylidene chloride. The content of the ethylenically unsaturated monomer, which is a copolymer, is about 40 to about 2 mass%, and is preferably about 35 to about 4 mass% from the balance between extrusion processability and gas barrier properties when forming a film from the resulting resin composition. As the ethylenically unsaturated monomer, vinyl chloride, vinyl acetate, vinyl propionate, alkyl acrylate, alkyl methacrylate, acrylic acid, methacrylic acid, itaconic acid or alkyl esters thereof, acrylonitrile, methacrylonitrile, acryl And diene unsaturated monomers such as monoethylenically unsaturated monomers such as amide, vinyl alkyl ether, vinyl alkyl ketone, acrolein, aryl ester and ether and styrene, butadiene and chloroprene. The vinylidene chloride copolymers (I) and (II) may be three or more copolymers obtained by copolymerizing two or more such ethylenically unsaturated monomers, but a binary copolymer is preferable. Among the ethylenically unsaturated monomers, preferably, vinyl chloride, alkyl acrylate and alkyl methacrylate having 1 to 8 carbon atoms of an alkyl group, for example, methyl acrylate, ethyl acrylate, methyl methacrylate, are listed. Vinyl chloride is more preferable since it is easy to have a balance between extrusion processability and gas barrier properties.

The vinylidene chloride copolymer (I) has a reduced viscosity in the range of more than 0.048 to 0.075, preferably in the range of more than 0.048 to 0.065, and more preferably in the range of 0.055 to 0.065. When the reduced viscosity of the vinylidene chloride copolymer (I) is higher than 0.075, resin decomposition products are generated and the extrusion workability deteriorates. In that case, in order to improve extrusion processability, additives, such as a liquid plasticizer and a stabilizer, must be added in large quantities. When a large amount of a liquid additive is added, it becomes easy to produce the adhesiveness of the film by the gas barrier property of the film obtained and the bleed of an additive. Moreover, it is preferable that the quantity of a liquid additive is 7 mass parts at most also in the resin composition of this invention. On the contrary, when the reduced viscosity of the vinylidene chloride copolymer (I) is 0.048 or less, the extrusion processability is good, but the stretchability decreases, and it is difficult to obtain a film having a stable thickness. When manufacturing a retort sausage, the meltability at the time of high frequency chamber falls, and the performances, such as a rupture at the time of filling, worsen. In addition, during retort sterilization, there may be a problem that the tensile strength (heat resistance) of the seal portion decreases, and that the rupture (puncture) from the seal portion increases.

The vinylidene chloride copolymer (II) preferably has a reduced viscosity in the range of 0.048 to 0.060, preferably less than 0.048 to 0.055, in view of the performance of the film, the retortability, and the extrudability of the vinylidene chloride copolymer resin composition. Do. The vinylidene chloride copolymer (II) suppresses the heat generation of the resin during extrusion and contributes to the improvement of extrusion processability, such as reduction of adhesion of resin decomposition products at the die outlet and reduction of fluctuations in the motor load of the extruder. If smaller, the performance and the retort performance decrease. When the reduced viscosity of vinylidene chloride copolymer (II) is in the range of 0.048 to 0.060, in order to achieve both performance and retort performance, the mixing ratio of vinylidene chloride copolymer (II) is vinylidene chloride copolymer. It is 50 mass% or less with respect to 100 mass% of sum total, More preferably, it is 3-25 mass%, Most preferably, it is the range of 5-25 mass%.

Thus, the resin composition of this invention which mixed the vinylidene chloride copolymer of the vinylidene chloride copolymer (I) and (II) of comparatively high viscosity and close reduction viscosity, is easy to melt uniformly in the extruder, and is shape | molded It is possible to reduce the occurrence of undesired cosmetic melt due to the quality of the film.

In addition, it is preferable that the composition ratio of vinylidene chloride of the vinylidene chloride copolymer (I) is larger than the composition ratio of vinylidene chloride of the vinylidene chloride copolymer (II) in view of performance and retort suitability.

In addition, the fish eye which makes the vinylidene chloride copolymer (I) and the vinylidene chloride copolymer (II) easily melt in the extruder and is produced by resin decomposition products, cosmetics, etc., which are undesirable in terms of the quality of the molded film. In order to reduce the occurrence of), the vinylidene chloride copolymer (I) and (II) are preferably homogeneous copolymers. Preferably, the vinylidene chloride copolymer (I) and the vinylidene chloride copolymer (II) are preferably binary copolymers of vinylidene chloride and vinyl chloride, respectively, for uniform melting of the resin.

The vinylidene chloride copolymers (I) and (II) may each consist of a mixture of two or more kinds of vinylidene chloride copolymers. In that case, each copolymer which comprises the vinylidene chloride copolymer (I) has a reduced viscosity in the range of more than 0.048-0.075, and similarly, each copolymer which comprises the vinylidene chloride copolymer (II) is vinylidene chloride It is necessary that the reduced viscosity is smaller than that of each copolymer constituting the copolymer (I) and is in the range of 0.048 to 0.060. It is for the same reason as the case where the reduced viscosity of the vinylidene chloride copolymer (II) mentioned above deviates.

Other polymers which may be added to the resin composition of the present invention in addition to the vinylidene chloride copolymer include ethylene and vinyl acetate copolymer, ethylene and acrylic acid, methacrylic acid or their alkyl esters (particularly alkyl esters having 1 to 4 carbon atoms). Ethylene-based copolymers and MBS resins are exemplified. Among these, it is preferable that ethylene content of an ethylene-based copolymer is 65-80 mass%, and MI (melt index) by JIS K-6730 is 5-40 g / 10min. Although the seal blow out at the time of retort is improved by adding these, 2.5 mass parts or less are preferable for the addition amount with respect to a total of 100 mass parts of vinylidene chloride copolymers. When it exceeds 2.5 mass parts, peeling will occur easily in a real part.

The MBS resin mainly comprises butadiene homopolymers or butadienes described in Japanese Patent Application Laid-Open No. 46-19550, and any one of styrene, methacrylic acid ester, acrylonitrile and vinylidene chloride alone or their A crosslinking agent copolymerizable with any mixture of 50 to 80 parts by weight of methyl methacrylate, styrene, vinylidene chloride alone or any mixture thereof in a flux containing 50 to 80 parts by weight of the rubber component. The BTA-1B SS by Kureha Chemical Co., Ltd. which contains the rubber plastic component obtained by post-polymerization in presence of 0.01-5 weight part etc. can be mentioned.

To the vinylidene chloride copolymer resin composition of the present invention, additives such as known plasticizers, heat stabilizers, processing aids, light stabilizers, pigments, lubricants, antioxidants, fillers, surfactants, and the like can be blended. . Specifically, as a liquid plasticizer, epoxidized soybean oil as a liquid stabilizer, such as dioctyl phthalate, acetyl tributyl citrate, diacetylated monoglyceride, dibutyl sebacate, dioctyl sebacate and diisobutyl adipate, Epoxidized oils such as epoxidized linseed oil and resins, such as amide derivatives of alkyl esters, magnesium hydroxide, tetrasodium pyrolate, magnesium oxide and calcium hydroxyphosphate, polyethylene oxide, paraffin wax, polyethylene wax, and montanic wax plasticizers, such as waxes such as ester waxes, heat stabilizers, processing aids, lubricants, fillers such as silicon oxide and calcium carbonate, sorbitan fatty acid esters, polyoxyethylene sorbitan fatty acid esters, and the like. Various additives, such as surfactant, can be mentioned. Titanium oxide pigments are effective in preventing discoloration of ultraviolet light in food contents such as sausage, but are liable to cause adhesion of resin decomposition products at die outlets. However, since this resin decomposition product is effectively reduced when extruded by a vacuum hopper mounting extruder, it is possible to add a large amount up to 0.10-10 mass parts.

Among the additives, the liquid plasticizer and the stabilizer are added in the range of about 1 to 10 parts by mass, and preferably 4 to 7 parts by mass with respect to 100 parts by mass in total of the vinylidene chloride copolymer. Some of these additives may be added during the polymerization of vinylidene chloride copolymer (I) or (II). The additive is adsorbed or absorbed by the vinylidene chloride copolymer during extrusion, contributing to extrusion processability. Additives other than liquid plasticizers and heat stabilizers are used as necessary.

The mixing method of the vinylidene chloride copolymer (I), (II) and the additive is not particularly limited, and a conventional method can be applied. For example, it is applicable by mixing by a blender, such as an impeller blender or a ribbon blender, by a Henschel high speed mixer, etc., or a heat mixing method over 60 degreeC, or a low temperature mixing method below 60 degreeC.

The vinylidene chloride copolymer resin composition obtained by mixing is extruded in a powder state or pellet form to be used for forming a film.

The recovered pulverized product (recycled resin) of the vinylidene chloride copolymer may be mixed with the powder and pellets of the vinylidene chloride copolymer for recycling. The mixing ratio of the pulverized product at this time is 10-50 mass% with respect to the sum total of vinylidene chloride copolymer (I) and (II), Preferably it is about 1-30 mass%. In the case where the recycled resin is mixed and extruded, extrusion with a vacuum hopper-mounted extruder suppresses the coloration and decomposition of the resin, and thus the extrusion processing method of the present invention is effective.

The vinylidene chloride copolymer resin composition of the present invention is melt-extruded into a stretched or unstretched film, a sheet or the like. As the molding method, as is known to those skilled in the art, for example, an inflation extrusion method using a circular die and the like are listed. Since the film obtained by orientation, especially preferably oriented by biaxial stretching, has heat shrinkability, it is suitably used as a shrink film or as a retort-resistant heat resistant film. As biaxial draw ratio, 2.0-4.5 times in a vertical direction and 3.0-5.0 times in a horizontal direction are preferable. The film thickness is 5-30 μm, preferably 10-25 μm as a single film. It is also used as a double film depending on a use. Usually, the thermal contraction rate is about 30 to about 60% (120 degreeC glycerin bath, 3 minutes) for both length and width | variety. The main method of use for food packaging is after inflation, two sheets overlapped and slit edge portions of the film as a double film, sealed in a cylindrical shape in a packing machine, filled with contents, and gripped at both ends. Used to get. In addition, the retort sterilization conditions are various, but generally sausages, depending on the diameter of the package, it is 10 to 20 minutes at approximately 120 ℃. Further, the film of the present invention can be laminated with a film made of another resin or resin composition which can be extruded together with the same type of resin or vinylidene chloride copolymer.

A second aspect of the present invention relates to an extrusion process for a vinylidene chloride copolymer resin composition. That is, when the vinylidene chloride copolymer resin composition is extruded, the resin composition is extruded by a vacuum hopper mounting extruder, whereby the extrudability is improved. In other words, the resin composition is extruded by a vacuum hopper-mounted extruder, which is effective in reducing the adhesion of the resin decomposition product at the die outlet, coloring of the resin and outflow of the decomposition product, reduction of the bursting of bubbles during inflation molding, and the like. The vacuum pressure of the vacuum hopper is mercury column -500 mm or less, preferably in the range of -600 mm to -755 mm. Extrusion processability can be improved by extruding the resin composition with an extruder equipped with a vacuum hopper set in such a condition.

The use of the titanium oxide pigment as described above increases the adhesion of the resin decomposition product of the die outlet, but the vacuum hopper is used in the present invention, which reduces it. Therefore, when the titanium oxide pigment is used, the extrusion processing method of the present invention is effective.

3rd of this invention is a film which consists of a vinylidene chloride copolymer resin composition provided by the 1st of this invention, Preferably it is a film manufactured by the 2nd extrusion process of this invention. Although this film was demonstrated simultaneously in the 1st of this invention, the said vinylidene chloride copolymer resin composition is arrange | positioned in a gas barrier layer, A multilayer film and a sheet are carried out by the coextrusion method and the lamination method. You can do

Example

Hereinafter, although an Example demonstrates this invention concretely, this invention is not limited by this.

(How to measure)

Reducing viscosity: 1 g of vinylidene chloride copolymer is added to 50 ml of tetrahydrofuran, dissolved at 40 DEG C, and after filtration, a polymer is precipitated with methanol, washed and dried. 80 mg of this dry polymer is precisely weighed, 20 ml of cyclohexanone at 30 ° C. is added as a solvent, heated and dissolved at 70 ° C. for 60 minutes, cooled at room temperature, filtered through a filter paper, and used as a sample solution for solution viscosity measurement. 5 ml of the sample solution was placed in a Ubbellohde viscometer, and left for 5 minutes in a 30 ° C. thermostatic bath, and then the flow time of the sample was measured and the reduced viscosity was determined by the following equation.

[Equation 1]

Reduced viscosity = (1/4) x {(T ₂ / T ₁ )-1}

T ₁ : Flowing time (in seconds) of cyclohexanone (solvent) at 30 ° C

T ₂ : Flowing time of the sample solution at 30 ° C.

Oxygen gas permeability: The oxygen gas permeability was measured at 30 ° C. and 100% relative humidity using an oxygen gas permeability measuring device (Ox-tran2 / 20 manufactured by Modern Control). The unit was cm ³ / m ² · day · atm and was measured by a double film (total thickness 40 μm).

Extrusion processability: Optical defect detection device (Hutech) for illuminating a traveling film (double film) having a total thickness of 40 μm and a width of 1250 mm with a light emitter, imaging a shadow of light with a light receiver, and detecting a foreign material by signal processing. Co., Ltd.) was used to irradiate foreign materials having a size of 0.5 mm x 0.5 mm over a film length of 1500 m. (Circle): 30 or less, (triangle | delta): 31-100 pieces, *: 101 or more measurement results were shown.

Retort seal punk: Automatic charging and ligation device with integrated film supply, high frequency sealing, automatic filling and ligation (KAP500 type, UHWA Chemical Engineering Co., Ltd.) ), A slit double film with a width of 70 mm was applied, and a center chamber was obtained by high frequency sealing to obtain a cylindrical film. 50 g of packed meat (sausage paste) was filled in the obtained cylindrical film as a filler, and the package which clipped both ends with the metal wire was obtained.

100 packages were placed in a tray, placed in a hot water retort tube (RCS-60 / 10 TG), and retorted for 15 minutes at a sterilization temperature of 133 ° C. . Thereafter, cooling water was added and cooled to obtain a retort package.

Each package was counted in the number of punctures from the seal. The evaluation result was represented by (circle): five or less puncture numbers, (triangle | delta): 6-10 or less puncture numbers, and x: 11 or more puncture numbers.

T-type peel strength of the yarn (a kind of performance): A retort-treated package, such as a yarn puncture, was retorted at 120 ° C. for 15 minutes and cooled to obtain a retort-treated package. In any one of the retort-treated packages, ten locations were selected from the entire seal portion in the longitudinal direction of the package, and the thread edge portions were held by fingers and peeled off to investigate the strength of the seal portions. The evaluation result was marked as (circle): it did not peel even if it tried to peel off, and x: peeled easily partially.

(Example 1)

Vinylidene chloride (VD) -vinyl chloride (VC) copolymer having a reduced viscosity of 0.056 (vinylidene chloride / vinyl chloride mass ratio by suspension polymerization: VD / VC = 88/12) {hereinafter referred to as PVDC1} 87% by mass, reduction Additive to 100 parts by mass of a vinylidene chloride-vinyl chloride copolymer having a viscosity of 0.052 (vinylidene chloride / vinyl chloride mass ratio: VD / VC = 82/18 by suspension polymerization) {hereinafter referred to as PVDC2} 13 mass% of a mixture As a total of 6 parts by mass of an epoxidized linseed oil and dibutyl sebacate, total of 1.7 parts by mass of an antioxidant, a lubricant and a red pigment were added to 100 parts by mass of the vinylidene chloride copolymer in total. Vinylidene chloride copolymer resin composition) was prepared. Subsequently, the compound was annularly melt-extruded in a 90 mm-diameter extruder equipped with a vacuum hopper (adjusted with a vacuum pressure of about -680 mm mercury), and then quenched by a conventional method in a 10 ° C. cooling bath and passed through a 20 ° C. hot water bath. Then, air was pushed in between the pinch rolls of two sets of rotational surface speeds which were expanded, and stretched to 2.8 times in the longitudinal direction and 3.7 times in the width direction. The thickness of the obtained film was 20 micrometers in single.

In the obtained film, the number of foreign matters in the film, oxygen permeation rate, retort yarn puncture, and T peel strength of the yarn were examined. The results are shown in Table-1.

(Example 2)

As another additive, it carried out similarly to Example 1 except having added glycerol monostearate. The powder drop from the vacuum hopper to the extruder was smooth and the load on the extruder was stabilized.

(Example 3)

In addition to the additive of Example 1, after mixing and cooling, the total amount of MI (melt index) = 15, vinyl acetate content 25 mass% ethylene and vinyl acetate copolymer (referred to as EVA-1) of vinylidene chloride copolymer 1 mass part was added with respect to 100 mass parts, it mixed at the temperature of 30 degreeC, and the compound (vinylidene chloride copolymer resin composition) was produced. Using this compound, extrusion was carried out as in Example 1 to obtain a film.

(Examples 4 to 5)

Vinylidene chloride (VD) -vinyl chloride (VC) copolymer having a reduced viscosity of 0.063 (vinylidene chloride / vinyl chloride mass ratio by suspension polymerization: VD / VC = 88/12) {hereinafter referred to as PVDC3} 80% by mass, reduction Example 1 except that it was a mixture of vinylidene chloride-vinyl chloride copolymer having a viscosity of 0.050 (vinylidene chloride / vinyl chloride mass ratio: VD / VC = 88/12 by suspension polymerization) (hereinafter referred to as PVDC6) 20% by mass. It carried out similarly to the film of Example 4 and Example 3, and obtained the film of Example 5.

(Comparative Example 1)

It carried out similarly to Example 1 except using only PVDC3 as resin composition and 9 mass parts as additives. As is apparent from the results shown in Table-1, the number of foreign matters in the film increased and the oxygen gas barrier property also decreased.

(Comparative Example 2)

Vinylidene chloride-vinyl chloride copolymer having a reduced viscosity of 0.058 (vinylidene chloride / vinyl chloride mass ratio by suspension polymerization: VD / VC = 88/12) {hereinafter referred to as PVDC5} 96% by mass of vinylidene chloride having a reduced viscosity of 0.040 Vinylidene chloride copolymer using 4 mass% of (VD) -vinyl chloride (VC) copolymer (vinylidene chloride / vinyl chloride mass ratio by suspension polymerization: VD / VC = 83/17) {hereinafter referred to as PVDC4} It carried out similarly to Example 1 except having used 6.8 mass parts of additives with respect to 100 mass parts of total amounts of. As is apparent from the results shown in Table-1, the retort seal puncture and oxygen gas barrier properties were also lowered.

(Comparative Example 3)

Example 1 except that 85 mass% of PVDC3 and 15 mass% of PVDC4 were used, and again 3 mass parts of EVA-1 and 5.5 mass parts of additives were used with respect to 100 mass parts of total vinylidene chloride copolymers as another copolymer. The same was done as. As is apparent from the results shown in Table-1, the number of foreign matters in the film increased, and the actual T peel strength also decreased.

(Examples 6 and 7)

In addition to the additive of Example 1, after mixing and cooling, MI (melt index) = 30, vinyl acetate content 33% by mass of ethylene and vinyl acetate copolymer (referred to as EVA-2) of vinylidene chloride copolymer 1.5 mass parts (Example 6) and 2.5 mass parts (Example 7) were added with respect to 100 mass parts of total amounts, it mixed at the temperature of 30 degreeC, and the compound (vinylidene chloride chloride resin composition) was produced. Using this compound, extrusion was carried out in the same manner as in Example 1 to obtain a film.

Example Comparative Example One 2 3 4 5 6 7 One 2 3 Resin composition (mass%) PVDC1PVDC2PVDC3PVDC4PVDC5PVDC6 8713 8713 8713 8020 8020 8515 8515 100 496 8515 (Mass part) * 3EVA-1EVA-2 One One 1.5 2.5 3 Manufacturing method * 1 Vacuum Hopper ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ Film Characteristics Extrusion Process Oxygen Gas Permeability * T-type Peeling Strength of Retort Seal Puncture Room ○ 32 ○○ ○ 32 ○○ ○ 30 ○○ △ 32 ○○ ○ 30 ○○ ○ 30 ○○ ○ 32 ○ △ △ 103 ○○ ○ 60 x ○ × 32 ○ ×

* 1: ○ indicates "used."

* 2: Oxygen gas permeability before retort.

* 3: Addition mass part with respect to 100 weight part of copolymers of PVDC in total.

According to the present invention, a vinylidene chloride copolymer resin composition which is excellent in extrusion processability and which provides a balanced film with respect to gas barrier properties, performance properties and retort properties is obtained. Moreover, such a characteristic can be improved further by the extrusion process which extrudes a vinylidene chloride copolymer resin composition with a vacuum hopper mounting extruder.

Claims (5)

It consists of 50 mass% or more of vinylidene chloride copolymers (I) and 50 mass% or less of vinylidene chloride copolymers (II), and the reduced viscosity of a vinylidene chloride copolymer (I) exceeds 0.048-0.075, and a vinylidene chloride air Vinylidene chloride copolymer resin composition, characterized in that the reduced viscosity of the copolymer (II) is in the range of 0.048 to 0.060 and the reduced viscosity of the vinylidene chloride copolymer (I) is larger than the vinylidene chloride copolymer (II). . The vinylidene chloride copolymer resin composition according to claim 1, wherein the vinylidene chloride copolymer (I) has a reduced viscosity in the range of 0.055 to 0.065. The vinylidene chloride copolymer resin according to claim 2, wherein the composition ratio of vinylidene chloride in the vinylidene chloride copolymer (I) is larger than that of vinylidene chloride in the vinylidene chloride copolymer (II). Composition. 4. The extrusion process method according to any one of claims 1 to 3, wherein the vinylidene chloride copolymer resin composition as claimed in claim 1 is extruded by a vacuum hopper mounting extruder. A film made from the vinylidene chloride copolymer resin composition as claimed in claim 1.