KR101786588B1 - Gas barrier resin composition for retort and product comprising the same - Google Patents

Abstract

The present invention relates to a retort gas composition comprising (a) an ethylene-vinyl alcohol copolymer and (b) a reactant of ethylene-maleic anhydride-alkyl methacrylate or ethylene-maleic anhydride-alkyl acrylate copolymer and polyamide oligomer To a barrier resin composition and a product containing the same.

Description

[0001] GAS BARRIER RESIN COMPOSITION FOR RETORT AND PRODUCT COMPRISING THE SAME [0002]

The present invention relates to a gas barrier resin composition for retort and a product containing the same. Specifically, the present invention relates to a gas barrier resin composition which does not cause whitening even after a sterilization process under high temperature and high humidity conditions and is excellent in gas barrier property, and a product containing the gas barrier resin composition.

The ethylene-vinyl alcohol copolymer (EVOH) is widely used as a food packaging material or other packaging material because of its excellent barrier property against gas such as oxygen. However, when retort treatment is carried out under high temperature and high humidity conditions for the purpose of sterilization by packing sap, medicine or milk products with packaging materials using an ethylene-vinyl alcohol copolymer, whitening may occur and the barrier property may be lowered An improvement in retortability is demanded.

As a method for improving the retort resistance of such an ethylene-vinyl alcohol copolymer, Korean Patent Laid-Open No. 10-2013-0016261 discloses a method of crosslinking an ethylene-vinyl alcohol copolymer. However, this method is disadvantageous in that a cross-linking step such as crosslinking of an electron beam is required, or a gel is generated when the processing temperature is high. In addition, U.S. Patent No. 8,039,114 discloses a method of adding a polyamide resin and an inorganic salt that acts as a drying agent to an ethylene-vinyl alcohol copolymer. However, the inorganic salt has a high moisture absorption rate with respect to moisture, so that it is difficult to control the storage of the composition, and care must be taken to uniformly distribute the inorganic salt in the preparation of the composition.

The present inventors have found that an ethylene-vinyl alcohol copolymer containing polyethylene, a copolymer of ethylene-maleic anhydride-alkyl methacrylate or ethylene-maleic anhydride-alkyl acrylate copolymer and a polyamide oligomer Although a mixture of reactants has been developed, the mechanical strength and transparency degradation are still not improved by the mixing of polyethylene, and the compatibility between ethylene-vinyl alcohol copolymer and polyethylene is insufficient, so that a film or sheet using these mixtures as a barrier layer The appearance is uneven, whitening occurs, and mechanical strength is low.

As a result of continuing research on this, the present inventors completed the present invention by developing a new composition which solves the above problems.

Korean Patent Publication No. 10-2013-0016261 U.S. Patent No. 8,039,114

In order to solve the above problems, it is an object of the present invention to provide a gas barrier resin composition which does not cause bleaching.

It is also an object of the present invention to provide a resin composition capable of producing a film, a sheet and a container having improved retort resistance and a product comprising at least one layer of the above composition.

It is another object of the present invention to provide a gas barrier resin composition and a product containing the gas barrier resin composition which are excellent in resistance to retort without any appearance problems even when the film or sheet is processed for a long period of time, The purpose.

In order to achieve the above object, the present invention relates to a gas barrier resin composition for retort and a product containing the same.

The gas barrier resin composition of the present invention comprises (a) an ethylene-vinyl alcohol copolymer and

(b) a reactant of an ethylene-maleic anhydride-alkyl methacrylate or an ethylene-maleic anhydride-alkyl acrylate copolymer and a polyamide oligomer.

Wherein the gas barrier resin composition comprises (a) 60 to 95% by weight of an ethylene-vinyl alcohol copolymer and (b) a copolymer of ethylene-maleic anhydride-alkyl methacrylate or ethylene-maleic anhydride- 5 to 40% by weight of the reactant of the amide oligomer.

The gas barrier resin composition may further comprise an ethylene-acrylic acid copolymer or an ethylene-methacrylic acid copolymer in an amount of 1 to 5 parts by weight based on 100 parts by weight of the total amount of the gas barrier resin composition.

The ethylene-acrylic acid copolymer or the ethylene-methacrylic acid copolymer may contain 80 to 99 mol% of ethylene and 1 to 20 mol% of acrylic acid or methacrylic acid.

The ethylene-vinyl alcohol copolymer may be obtained by saponifying 90 to 99.9 mol% of ethylene-vinyl acetate having an ethylene content of 10 to 50 mol%.

The reactant of the ethylene-maleic anhydride-alkyl methacrylate or ethylene-maleic anhydride-alkyl acrylate copolymer and the polyamide oligomer may be in a weight ratio of 10:90 to 50:50.

The ethylene-maleic acid-alkyl methacrylate or ethylene-maleic acid-alkyl acrylate copolymers are C ₁ -C ₂₀ alkyl methacrylates and C ₁ -C _20, including polymerizing a monomer selected from alkyl acrylates .

The ethylene-maleic anhydride-alkyl methacrylate or ethylene-maleic anhydride-alkyl acrylate copolymer is prepared by copolymerizing ethylene with 65 to 94 mol%, maleic anhydride with 0.1 to 5 mol% and alkyl methacrylate or alkyl acrylate with 5 to 20 mol% 30 mole%.

The ethylene-maleic anhydride-alkyl methacrylate or ethylene-maleic anhydride-alkyl acrylate copolymer may have a melt index (MI) of 0.1 to 10 g / 10 min measured at 190 ° C under a load of 2.16 kg.

The polyamide oligomer may be selected from the group consisting of polyamide-6, polyamide-6,6, polyamide-4,6, polyamide-11, polyamide-12, polyamide-6,10, polyamide- 6 / 6,6, polyamide-6 / 6,12, polyamide MXD, 6, polyamide-6, T, polyamide-6, I, polyamide- Polyamide-6,6 / 6, T, polyamide-6,6 / 6, I, polyamide-6/6, T / 6, I, polyamide- I, polyamide-6/12/6, T, polyamide-6,6 / 12/6, T, polyamide-6/12 / And copolymers thereof. ≪ / RTI >

The polyamide oligomer may have a weight average molecular weight of 500 to 5,000 g / mol.

May be a gas barrier layer made of the gas barrier resin composition.

And may be a gas barrier film containing one or more of the gas barrier layers.

And a gas barrier sheet comprising one or more of the gas barrier layers.

Barrier ribs which contain one or more gas barrier layers.

The gas barrier resin composition and the product containing the same according to the present invention are excellent in gas permeability, workability and fogging as well as excellent in retortability, and are excellent in gelation and lowered moldability There is an advantage that there is no.

Hereinafter, the gas barrier resin composition and the product containing the same according to the present invention will be described in more detail by way of examples. It should be understood, however, that the invention is not limited to the disclosed embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the invention.

Unless otherwise defined, all technical and scientific terms have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

In addition, the unit of the additives not specifically described in the specification may be% by weight.

In the present invention, the term " orange peel " means that the surface of an article such as a layer, a film, a sheet and a container formed by applying a gas barrier resin composition during processing has a different heat shrinkage rate, . It becomes a very important quality factor which should not be shown in the present invention.

In the present invention, the term " retort " refers to a single layer film or sheet, a metal foil or a curly, a rice, a jelly, a porridge, a soup, or the like made into a product such as a multi- It can be edible by direct or simple cooking method by filling, sealing, pressurizing, heating, sterilizing or sterilizing the medical solution such as food or liquid such as hot water, hot water, stew, hotpot, soup, And to manufacture products that can store foods to facilitate transportation.

The present invention relates to a gas barrier resin composition and a product containing the same.

The present invention will be described in detail,

The gas barrier resin composition of the present invention comprises (a) an ethylene-vinyl alcohol copolymer and

(b) a reactant of an ethylene-maleic anhydride-alkyl methacrylate or an ethylene-maleic anhydride-alkyl acrylate copolymer and a polyamide oligomer.

The gas barrier resin composition according to one embodiment of the present invention comprises (a) 60 to 95% by weight of an ethylene-vinyl alcohol copolymer and (b) ethylene-maleic anhydride-alkyl methacrylate or ethylene- Acrylate copolymer and a polyamide oligomer in an amount of 5 to 40% by weight.

In the present invention, (a) the ethylene-vinyl alcohol (EVOH) copolymer is a random copolymer, but may be prepared by a method of saponifying ethylene-vinyl acetate produced by copolymerization of ethylene and vinyl acetate with caustic soda. In the ethylene-vinyl alcohol copolymer, the physical properties may vary greatly depending on the copolymerization ratio of ethylene and vinyl alcohol.

The ethylene-vinyl alcohol copolymer of the present invention may be obtained by saponifying 90 to 99.9 mol% of ethylene-vinyl acetate having an ethylene content of 10 to 50 mol%, but is not limited thereto.

When the ratio of ethylene in the ethylene-vinyl alcohol copolymer is within the above range, the processability is excellent and the humidity dependency at high humidity is reduced, so that the gas barrier property is good. Utilizing these advantages, the ethylene-vinyl alcohol copolymer can be used as a gas barrier material such as a single layer film, a multilayer film, a sheet, and a bottle.

The gas barrier resin composition may further comprise 1 to 5 parts by weight of an ethylene-acrylic acid copolymer or an ethylene-methacrylic acid copolymer based on 100 parts by weight of the total amount of the gas barrier resin composition.

When the ethylene-acrylic acid copolymer or the ethylene-methacrylic acid copolymer is further contained, it is preferable that the gas barrier property is further improved and transparency is improved.

The ethylene-acrylic acid copolymer or ethylene-methacrylic acid copolymer may contain 80 to 99 mol% of ethylene, 1 to 20 mol% of acrylic acid or methacrylic acid, but is not limited thereto. When the content is included in the above range, the gas barrier property is excellent and the transparency is more preferably increased.

The ethylene-vinyl alcohol copolymer is excellent in gas barrier property when the ethylene vinyl acetate is saponified within the above range. And more preferably 95 to 99.9 mol%, but is not limited thereto.

Although the ethylene-vinyl alcohol copolymer is excellent in gas barrier property, whitening occurs when the product is used for retort. Thus, in the present invention, a product for a retort was prepared by mixing a reactant of ethylene-maleic anhydride-alkyl methacrylate or an ethylene-maleic anhydride-alkyl acrylate copolymer and a polyamide oligomer, and the whitening phenomenon was remarkably reduced.

The reactant of the ethylene-maleic anhydride-alkyl methacrylate or ethylene-maleic anhydride-alkyl acrylate copolymer of the present invention and the polyamide oligomer may be in a weight ratio of 10:90 to 50:50. With the reaction ratio within the above range, it is possible to prevent the mechanical strength from lowering due to the excessive amount of the polyamide oligomer during the reaction.

Also, the above-mentioned ethylene-maleic anhydride-alkyl methacrylate or ethylene-maleic anhydride-alkyl acrylate copolymer and a polyamide oligomer may be mixed and melt-extruded. Specific examples thereof include, but are not limited to, dry blending followed by melt extrusion using equipment such as a Brabender mixer, single- or twin-screw extruder .

The ethylene-maleic anhydride-alkyl methacrylate or the ethylene-maleic anhydride-alkyl acrylate copolymer and the polyamide oligomer are melt-extruded and mixed with ethylene-maleic anhydride-alkyl methacrylate or ethylene-maleic anhydride- Rate copolymer can react with an amine group which is a terminal group of the polyamide and can act as a modifier that can improve physical properties such as whitening and gas barrier properties.

In particular, the reaction with ethylene-maleic anhydride-alkyl methacrylate or ethylene-maleic anhydride-alkyl acrylate copolymer and polyamide oligomer is directly minimized with the ethylene-vinyl alcohol copolymer, It is possible to improve the retort resistance even when the present invention does not cause a whitening phenomenon and has excellent melt processability, appearance and mechanical properties of a molded product, and is excellent in retort resistance.

Anhydrous maleic acid-ethylene of the present invention, the alkyl acrylate copolymer is a monomer selected from C ₁ -C ₂₀ alkyl methacrylates and C ₁ -C ₂₀ alkyl acrylate-alkyl methacrylate or ethylene-maleic acid May be polymerized. The copolymer may be produced by radical copolymerization of ethylene, maleic anhydride with C ₁ -C ₂₀ alkyl methacrylate or C ₁ -C ₂₀ alkyl acrylate.

The ethylene-maleic anhydride-alkyl methacrylate or ethylene-maleic anhydride-alkyl acrylate copolymer is prepared by copolymerizing ethylene with 65 to 94 mol%, maleic anhydride with 0.1 to 5 mol% and alkyl methacrylate or alkyl acrylate with 5 to 20 mol% 30 mole%.

When the maleic anhydride having a functional group important for causing the reaction with the polyamide oligomer at the above ratio of the ratio of ethylene to maleic anhydride, alkyl methacrylate or alkyl acrylate is 0.1 to 5 mol% in the copolymer The crosslinking reaction is suppressed during the production of the composition, so that the melt processability is improved and the appearance defects such as whitening phenomenon can be reduced.

When the ratio of alkyl methacrylate or alkyl acrylate in the copolymer is in the range of 5 to 30 mol%, the alkyl methacrylate or alkyl acrylate decreases not only the transparency but also the transparency by decreasing the crystallinity of the copolymer. By having a low melting temperature, the produced modifier has good flowability when it is melted in the composition, so that appearance defects such as gel generation can be prevented.

The ethylene-maleic anhydride-alkyl methacrylate or ethylene-maleic anhydride-alkyl acrylate copolymer may have an ethylene content other than the ratio of maleic anhydride to alkyl methacrylate or alkyl acrylate.

The ethylene-maleic anhydride-alkyl methacrylate or ethylene-maleic anhydride-alkyl acrylate copolymer of the present invention may have a melt index (MI) of 0.1 to 10 g / 10 min measured at 190 ° C. under a load of 2.16 kg But is not limited thereto. When the melt index is in the above range, the melt processability is excellent, gas barrier properties are excellent, and the occurrence of whitening can be prevented.

The ethylene-maleic anhydride-alkyl methacrylate or ethylene-maleic anhydride-alkyl acrylate copolymer of the present invention may be, but is not limited to, a random copolymer for the overall uniform reaction. For example, it may be a random copolymer such as ethylene-maleic anhydride-methylacrylate, ethylene-maleic anhydride-butyl acrylate, ethylene-maleic anhydride-ethyl acrylate, ethylene-maleic anhydride-methacrylate Specific examples thereof include, but are not limited to, Lotader (R) MAH Grades 3210, 3410, 4210, 3430, 4403, 4503, 4613, 4700, 5500, LX4110, TX8030 and the like manufactured by Arkema.

Grafted copolymers prepared by adding peroxide and maleic anhydride to an olefin-based copolymer in addition to the random copolymers, and grafting maleic anhydride, for example, ethylene-methyl acrylate grafted with maleic anhydride However, in the case of olefin copolymers grafted with maleic anhydride, the reaction site with the polyamide oligomer is small, and when the obtained reaction product is blended with the ethylene-vinyl alcohol copolymer, a gel may be generated. - maleic anhydride-alkyl (meth) acrylate is used, the maleic anhydride is copolymerized to form the main chain of the polymer, thereby partially suppressing the reaction of the maleic anhydride unit and the ethylene-vinyl alcohol copolymer Gel generation can be minimized.

In the polyamide oligomer of the present invention, the polyamide oligomer is selected from the group consisting of polyamide-6, polyamide-6,6, polyamide-4,6, polyamide-11, polyamide-12, polyamide- Amide-6,12, polyamide 6/6, polyamide-6 / 6,12, polyamide MXD, 6, polyamide-6, T, polyamide- I, polyamide-6,6 / 6, T, polyamide-6,6 / 6, I, polyamide-6/6, T / Polyamide-6/12/6, T, polyamide-6/12/6, T, , 6/12/6, I, and copolymers thereof, but is not limited thereto.

The polyamide oligomer may be prepared by adding a molecular weight modifier in the course of preparing polyamide, but is not limited thereto. As the molecular weight regulator, an aliphatic alcohol, an aliphatic amine, an aromatic alcohol, an aromatic amine, or a polyether oligomer compound may be used. Preferred examples of primary amines include primary aliphatic amines such as nonylamine, decylamine and dodecylamine, and primary amines such as benzylamine, alpha-phenylethylamine and beta-phenylethylamine, and amines substituted in the ring Derivatives thereof, and mixtures thereof.

The polyamide oligomer of the present invention may have a weight average molecular weight of 500 to 5,000 g / mol. More preferably a weight average molecular weight of 1,000 to 4,000 g / mol, but is not limited thereto. When the weight average molecular weight of the polyamide oligomer is within the above range, the probability of reaction with the copolymer containing maleic anhydride increases due to excellent flow properties upon melt extrusion, thereby exerting the excellent effect of the present invention. Also, the mechanical and thermal properties according to the composition of the present invention are preferably improved.

The gas barrier resin composition of the present invention may be mixed with an extruder after being subjected to dry blending or melt blending according to the production conditions of the product to produce a molded product. Dry mixing may be performed using equipment such as a tumbler mixer, and melt mixing may be performed using equipment such as a blender mixer, single shaft or twin screw extruder.

And a gas barrier layer made of the gas barrier resin composition of the present invention. The gas barrier layer is capable of stably maintaining gas barrier properties without causing whitening even in an environment such as pressurization and storage at a high temperature. The gas barrier layer can be maintained under severe conditions such as retort treatment conditions of 120 DEG C / 30 min or more Means a layer included in a product for packaging a novel retort food which has thermal stability and maintains dimensional stability.

Products such as single-layer or multilayer films, sheets, containers and the like which are excellent in gas barrier properties, melt processability and fogging, and which do not cause retort whitening phenomenon, including a gas barrier layer obtained from the gas barrier resin composition .

The gas barrier layer can be produced by processing the gas barrier resin composition of the present invention using a processing apparatus such as blown casting or cast extrusion molding, but is not limited thereto.

For example, the gas barrier resin composition of the present invention may be laminated to A, the adhesive resin may be laminated to B, and the thermoplastic resin may be laminated to C in various configurations according to an embodiment of the present invention. A / B / A / B / C / B / A / B, C / B / A / B / C, C / / A / C / B / C, or the like, but is not limited thereto. Other functional layers such as a sealant layer may be further included, but the present invention is not limited thereto. The multilayer film according to the above embodiment is excellent in gas barrier properties such as oxygen and water vapor by including the gas barrier layer and exhibits an excellent effect that whitening does not occur even under retort conditions, no.

As the adhesive resin, for example, a resin obtained by grafting a polyolefin resin such as polyethylene or polypropylene with an unsaturated acid such as maleic acid can be used. As a concrete example, the adhesive resin is for enhancing the adhesive force at the interface between the layers of the multilayer film, and can be applied to prevent phase separation between the layers.

(MAH-g-LDPE), maleic anhydride-grafted linear low density polyethylene (MAH-g-LLDPE), maleic anhydride grafted high density polyethylene (MAH-g-LDPE), and maleic anhydride- g-HDPE), maleic anhydride-grafted ethylene vinyl acetate (MAH-g-EVA), and the like, but the present invention is not limited thereto.

As the thermoplastic resin, polyethylene, polypropylene, polystyrene, polyamide or the like may be used for imparting the flexibility and basic mechanical strength of the multilayered film, but the present invention is not limited thereto.

In the gas barrier resin composition of the present invention, additives such as processing aids, dyes, antioxidants, light stabilizers, and plasticizers may be used as needed, and copolymers of polyethylene or ethylene and alpha olefins, monomers having ethylene and carbonyl groups A copolymer, a polypropylene, an ethylene-propylene copolymer, a polyamide, a polyester and the like may be further added and used, but the present invention is not limited thereto.

Products such as films produced according to the present invention may be subjected to crosslinking treatment by a method such as electron beam irradiation in order to improve heat resistance as required.

  The multilayer film according to an embodiment of the present invention may be laminated by coextrusion, but is not limited thereto.

Since the co-extruder co-extrudes two or more layers of resin or resins composed of the same component or extruded into two or more layers depending on the number and structure of the extruder, It is very efficient in giving functionality.

In the present invention, co-extrusion can be carried out in a coater such as a tie die, a blower and a tubular type extruder according to a desired product thickness at the time of co-extrusion, and a uniaxial extruder or a twin screw extruder can be freely selected depending on the form and use of the product . If the melting temperature is lower than the temperature range during extrusion, the interlaminar adhesive strength is lowered. If the temperature is higher than the above range, the molding stability may be deteriorated or a thermal decomposition product or gel may be generated.

The temperature conditions for extrusion of the present invention are not particularly limited depending on the kind and content of the composition. For example, the thermoplastic resin may be 190 to 220 占 폚, the adhesive layer including the adhesive resin may be 190 to 220 占 폚, the gas barrier layer may be 200 to 250 占 폚, and the sealant layer may be 190 to 230 占 폚, but the present invention is not limited thereto .

The gas barrier resin composition for retort according to the present invention and the product containing the same will be described in more detail with reference to the following examples. It should be understood, however, that the invention is not limited to the disclosed embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the invention.

Unless otherwise defined, all technical and scientific terms have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

In addition, the unit of the additives not specifically described in the specification may be% by weight.

[Measurement of physical properties]

1) Haze

- Measured by the ASTM D1003 method using a NIPPON DENSHOKU 300A Turbidimeter analyzer in Japan.

[Formula 1]

Cloudiness value (%) = (diffusion transmittance (Td) / total light transmittance (Tt)) x 100

In the above equation, the total light transmittance (Tt) is a value corresponding to the sum of the diffuse transmittance and the parallel transmittance. The diffusion transmittance Td is a value obtained by subtracting the parallel transmitted light from the total light transmittance.

2) Melt index (MI, Melt index)

Measured by applying a force of 2.16 kg at 190 캜 or 230 캜 according to ASTM D1238, and the unit is g / 10 min.

3) Density

The density was measured according to ASTM D-1505, and the unit is g / cm3.

4) Whitening phenomenon

After the film was sealed with heat, it was placed in an autoclave together with water, heated to 121 DEG C, taken out after 30 minutes, and its degree was displayed as follows.

(1: no whitening phenomenon observed,

2 ~ 4: The degree of bleaching was observed from the end of the heat sealing to show the degree of penetration into the inside. The larger the number,

5: The whitening occurs at the end of the heat sealing and the unsealed part.)

5) Weight average molecular weight

GPC Column: TSKgel SuperMultipore Hz-N (Tosoh Corporation)

Column temperature: 40 ° C

Solvent: tetrahydrofuran (THF)

Flow rate: 1 ml / min

Standard samples: Polystyrene (Tosoh Corporation)

The types of ethylene-vinyl alcohol copolymer and ethylene-acrylic acid copolymer (a) used in the experiments of the present invention are shown in Table 1 below.

 (a) Component   Resin type   The melt viscosity (2.16 kg, g / 10 min, 190 캜)   Density (g / cm3) A-1   EVOH, an ethylene content of 38 mol% 1.8 1.17 A-2   EVOH, an ethylene content of 32 mol% 1.7 1.19 A-3   Ethylene-acrylic acid copolymer, 9.7 mol% of acrylic acid, 1.0 0.94

[Production Example 1]

Preparation of polyamide oligomer (PAO)

1.7 kg of caprolactam, 109 g of dodecylamine and 39 g of water were sealed in a 5 L capacity pressurized reactor and reacted with stirring at 260 DEG C for 2 hours. At this time, the pressure of the pressure reactor was increased to 4.5 kg / cm 2.

The pressure regulating valve was opened and the pressure was adjusted to normal pressure. Then, the reaction was continued at 260 ° C for 2 hours and the temperature was dropped to room temperature to obtain a solid component. These solid components were pulverized in a pulverizer to prepare a powder, stirred in boiling water for 2 hours, filtered and dried in a vacuum oven at 80 DEG C for 8 hours. The melting temperature of the obtained polyamide oligomer was 210 ° C. The terminal amine group was measured by an acid base titration method and found to have a degree of polymerization of 23 and a weight average molecular weight of 2,800 g / mol.

The kinds of the component (b) used in the experiment are shown in Table 2 below.

(b) Component Resin type B-1 Ethylene-maleic anhydride-methyl acrylate random copolymer
(Arkema Lotader 3430) 15% by weight of methyl acrylate,
3.1% by weight of maleic anhydride,
The melt viscosity (melt index measured at 190 占 폚 under a load of 2.16 kg: 6.0 g / 10 min) B-2 Ethylene-maleic anhydride-butyl acrylate random copolymer
(Arkema Lotader 3410) 17% by weight of butyl acrylate,
3.1% by weight of maleic anhydride,
The melt viscosity (melt index measured at 190 占 폚 under a load of 2.16 kg: 5.0 g / 10 min) B-3 Ethylene-maleic anhydride-ethyl acrylate random copolymer
(Arkema Lotader 5500) 17% by weight of butyl acrylate,
3.1% by weight of maleic anhydride,
The melt viscosity (melt index measured at 190 占 폚 under a load of 2.16 kg: 20 g / 10 min) B-4 Ethylene-methyl acrylate copolymer grafted with maleic anhydride
(DuPont Bynel 21E830) The melt viscosity (melt index measured at 190 占 폚 at a load of 2.16 kg: 7.7 g / 10 min)
Density 0.94 g / cm < 3 & B-5 B-1 / PAO = 30/70 weight ratio reactant The melt viscosity (melt index measured at 190 占 폚 under a load of 2.16 kg: 3.2 g / 10 min) B-6 B-2 / PAO = 40/60 weight ratio reactant The melt viscosity (melt index measured at 190 占 폚 under a load of 2.16 kg: 1.5 g / 10 min) B-7 B-2 / PAO = 30/70 weight ratio reactant The melt viscosity (melt index measured at 190 占 폚 at a load of 2.16 kg: 1.1 g / 10 min) B-8 B-2 / PAO = 20/80 weight ratio reactant The melt viscosity (melt index measured at 190 占 폚 at a load of 2.16 kg: 1.0 g / 10 min) B-9 B-2 / PAO = 10/90 weight ratio reactant The melt viscosity (melt index measured at 190 占 폚 under a load of 2.16 kg: 0.8 g / 10 min) B-10 B-3 / PAO = 30/70 weight ratio reactant The melt viscosity (melt index measured at 190 占 폚 under a load of 2.16 kg: 6.0 g / 10 min) B-11 B-4 / PAO = 30/70 weight ratio reactant  The melt viscosity (melt index: measured at 190 占 폚 under a load of 2.16 kg: 1.8 g / 10 min) B-12 B-4 / PAO = 70/30 weight ratio reactant  The melt viscosity (melt index measured at 190 占 폚 at a load of 2.16 kg: 2.1 g / 10 min) B-13 B-1 / PAO = 70/30 weight ratio reactant  The melt viscosity (melt index measured at 190 占 폚 under a load of 2.16 kg: 2.5 g / 10 min)

[Production Example 2]

Preparation of Modifiers B-4 to B-7 Reactants of Copolymer of Ethylene-Maleic Anhydride-alkyl Methacrylate or Ethylene-Maleic Anhydride-alkyl Acrylate of the Present Invention with Polyamide Oligomer:

After dry blending the mixture at the weight ratios shown in Table 2, the mixture was melt-extruded at 180-200-220-240-260-250 ° C using a twin screw extruder having a diameter of 19 mm Pellets.

[Example 1]

Multilayer films were prepared using pneumatic actuators having five melt extruders of 60/50/50/50/60 mm respectively. At this time, the multilayer film was composed of an outer layer, an adhesive layer, a gas barrier layer, an adhesive layer, and a sealant layer laminated in a total thickness of 90/10 ㎛ in a thickness of 25/10/15/8/32 ㎛.

The outer layer was made of linear low density polyethylene (melt index: 0.75 g / 10 min, density: 0.919 g / cm3, SKGC FN812 measured at 190 占 폚 under a load of 2.16 kg) at 190 占 폚 under the temperature condition of the extruder.

(Melt index: 1.2 g / 10 min, density: 0.919 g / cm 3, measured at 190 ° C under a load of 2.16 kg) in which maleic anhydride grafted with an adhesive layer adjacent to the outer layer was grafted was heated to 190 ° C .

Dry mixed in a 80/20 weight%: (183 ℃, F171B, EVAL.co. 32 mole% ethylene content, T _m) and B-5 wherein each of the gas barrier layer with a composition of the present invention is a copolymer of ethylene vinyl alcohol And then put into an extruder.

A polypropylene adhesive resin (melt index: 3.0 g / 10 min, density: 0.90 g / cm 3, Admer QB516, measured at a load of 2.16 kg at 230 캜, Mitsui, Admer QB516) was used as an adhesive layer adjacent to the sealant layer. ≪ / RTI >

(Melt index: 1.8 g / 10 min, density: 0.90 g / cm 3, R520Y of ethylene random copolymer SKGC measured at a load of 2.16 kg at 230 캜) as the sealant layer was set at 210 캜 Respectively.

Examples 2 to 21 and Comparative Examples 1 to 12 were carried out under the same conditions as in Example 1, except that the gas barrier layer resin compositions of the gas barrier layers were different in kind and content ratio. Respectively. However, Example 21 further contains 3 parts by weight of an ethylene-acrylic acid copolymer with respect to 100 parts by weight of the gas barrier resin composition of the gas barrier layer.

Composition ratio (% by weight)  Oxygen permeability (cc / ㎡ .day) Processability Cloudiness
(Haze,%)  Retort whitening Example 1 A-2 / B-5 = 80/20 1.5 Good 15 One Example 2 A-2 / B-6 = 80/20 1.2 Good 16 One Example 3 A-2 / B-7 = 80/20 1.3 Good 15 One Example 4 A-2 / B-8 = 80/20 1.2 Good 14 One Example 5 A-2 / B-9 = 80/20 1.4 Good 13 One Example 6 A-2 / B-10 = 80/20 2.0 Good 18 2 Example 7 A-2 / B-13 = 80/20 1.6 Surface unevenness 17 3 Example 8 A-2 / B-5 = 70/30 1.7 Good 16 One Example 9 A-2 / B-6 = 70/30 1.8 Good 14 One Example 10 A-2 / B-7 = 70/30 2.1 Good 15 One Example 11 A-1 / B-5 = 80/20 2.3 Good 17 One Example 12 A-1 / B-6 = 80/20 2.5 Good 14 One Example 13 A-1 / B-7 = 80/20 2.2 Good 15 One Example 14 A-1 / B-8 = 80/20 2.5 Good 16 One Example 15 A-1 / B-9 = 80/20 2.0 Good 14 One Example 16 A-1 / B-10 = 80/20 3.1 Good 16 2 Example 17 A-1 / B-13 = 80/20 4.7 Surface unevenness 25 3 Example 18 A-1 / B-5 = 70/30 2.7 Good 14 One Example 19 A-1 / B-6 = 70/30 2.2 Good 15 One Example 20 A-1 / B-7 = 70/30 2.3 Good 14 One Example 21 A-1 / A-3 / B-5
= 80/3/20 1.8 Good 14 One Comparative Example 1 A-1 = 100 1.1 Good 11 5 Comparative Example 2 A-2 / B-11 = 80/20 4.4 Gel generation 23 3 Comparative Example 3 A-2 / B-12 = 80/20 4.5 Gel generation 25 4 Comparative Example 4 A-1 / B-11 = 80/20 4.2 Gel generation 16 3 Comparative Example 5 A-1 / B-12 = 80/20 4.3 Gel generation 24 4 Comparative Example 6 A-2 / B-1 = 80/20 4.7 Orange peel 23 3 Comparative Example 7 A-2 / B-2 = 80/20 3.5 Orange peel 20 4 Comparative Example 8 A-2 / B-3 = 80/20 4.9 Orange peel 22 4 Comparative Example 9 A-2 / B-4 = 80/20 4.6 Gel generation 26 4 Comparative Example 10 A-1 / B-1 = 80/20 4.8 Orange peel 24 3 Comparative Example 11 A-1 / B-2 = 80/20 3.7 Orange peel 21 4 Comparative Example 12 A-1 / B-3 = 80/20 4.9 Orange peel 25 4

As shown in the above Table 3, it was confirmed that the gas barrier resin composition of the present invention of the present invention markedly reduced the whitening phenomenon at the time of retorting when the ethylene-vinyl alcohol polymer of Comparative Example 1 was used alone, , The gas permeability was excellent, and the workability and fog were not deteriorated.

It was confirmed that the gas barrier properties of the ethylene-vinyl alcohol copolymer itself were lowered in the comparative example, and the effect of improving the whitening phenomenon was remarkably lower than that of the examples.

The melt index (MI) of the ethylene-maleic anhydride-alkyl methacrylate or ethylene-maleic anhydride-alkyl acrylate copolymer as the component (b) measured at 190 ° C under a load of 2.16 kg is 0.1 to 10 g / 10min, it was found that the whitening phenomenon prevention, workability, fogging and gas permeability were more excellent.

In addition, it was confirmed that when the gas barrier resin composition of the gas barrier layer further contains an ethylene-acrylic acid copolymer, the gas barrier property is further improved and the transparency is further superior.

Accordingly, the gas barrier resin composition and the product containing the same of the present invention are excellent in gas barrier properties under the conditions of high temperature and high pressure and under the retort conditions, and are excellent in appearance defects such as whitening, orange peel, It can be applied to products for retort.

As described above, the gas-barrier resin composition for retort and the product containing the same are described in the present invention through specific matters and a limited embodiment. However, the present invention is provided for better understanding of the present invention, It will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

Accordingly, the spirit of the present invention should not be construed as being limited to the embodiments described, and all of the equivalents or equivalents of the claims, as well as the following claims, belong to the scope of the present invention .

Claims (15)

(a) an ethylene-vinyl alcohol copolymer and
(b) a reaction product of an ethylene-maleic anhydride-alkyl methacrylate or an ethylene-maleic anhydride-alkyl acrylate copolymer and a polyamide oligomer,
Wherein the reactant of the ethylene-maleic anhydride-alkyl methacrylate or the ethylene-maleic anhydride-alkyl acrylate copolymer and the polyamide oligomer is in a weight ratio of 10:90 to 40:60. The method according to claim 1,
Wherein the gas barrier resin composition comprises (a) 60 to 95% by weight of an ethylene-vinyl alcohol copolymer and (b) an ethylene-maleic anhydride-alkyl methacrylate or an ethylene-maleic anhydride-alkyl acrylate copolymer and a polyamide 5 to 40% by weight of the oligomer reactant,
Based resin composition. The method according to claim 1,
Wherein the gas barrier resin composition further comprises 1 to 5 parts by weight of an ethylene-acrylic acid copolymer or an ethylene-methacrylic acid copolymer based on 100 parts by weight of the total amount of the gas barrier resin composition. The method of claim 3,
Wherein the ethylene-acrylic acid copolymer or ethylene-methacrylic acid copolymer comprises 80 to 99 mol% of ethylene and 1 to 20 mol% of acrylic acid or methacrylic acid. The method according to claim 1,
Wherein the ethylene-vinyl alcohol copolymer is obtained by saponifying 90 to 99.9 mol% of ethylene-vinyl acetate having an ethylene content of 10 to 50 mol%. delete The method according to claim 1,
The ethylene-maleic acid-alkyl methacrylate or ethylene-maleic acid-alkyl acrylate copolymers are C ₁ -C ₂₀ alkyl methacrylates and C ₁ -C _20, including polymerizing a monomer selected from alkyl acrylates By weight based on the total weight of the composition. The method according to claim 1,
Wherein the ethylene-maleic anhydride-alkyl methacrylate or ethylene-maleic anhydride-alkyl acrylate copolymer is a copolymer of ethylene and maleic anhydride in an amount of 65 to 94 mol% ethylene, 0.1 to 5 mol% maleic anhydride, And 30 mol% of the total amount of the composition. The method according to claim 1,
Wherein said ethylene-maleic anhydride-alkyl methacrylate or ethylene-maleic anhydride-alkyl acrylate copolymer has a gas barrier property resin (MI) having a melt index (MI) of 0.1 to 10 g / 10 min measured at 190 DEG C under a load of 2.16 kg Composition. The method according to claim 1,
The polyamide oligomer may be selected from the group consisting of polyamide-6, polyamide-6,6, polyamide-4,6, polyamide-11, polyamide-12, polyamide-6,10, polyamide- 6 / 6,6, polyamide-6 / 6,12, polyamide MXD, 6, polyamide-6, T, polyamide-6, I, polyamide- Polyamide-6,6 / 6, T, polyamide-6,6 / 6, I, polyamide-6/6, T / 6, I, polyamide- I, polyamide-6/12/6, T, polyamide-6,6 / 12/6, T, polyamide-6/12 / And a copolymer of any of them. The method according to claim 1,
Wherein the polyamide oligomer has a weight average molecular weight of 500 to 5,000 g / mol. A gas barrier layer made of the gas barrier resin composition according to any one of claims 1 to 5 and 7 to 11. A gas barrier film comprising one or more gas barrier layers of claim 12. A gas barrier sheet comprising one or more gas barrier layers of claim 12. A gas barrier container comprising one or more gas barrier layers of claim 12.