Gas barrier resin composition, method for producing gas barrier resin composition, and molded product

Patent metadata

Field	Value
Publication number	US-12460074-B2
Application number	US-202118012792-A
Country	US
Kind code	B2
Filing date	Jun 29, 2021
Priority date	Jun 30, 2020
Publication date	Nov 4, 2025
Grant date	Nov 4, 2025

Abstract

Provided are: a gas barrier resin composition having sufficient long-run workability and superior gas barrier properties which compare favorably to those of fossil fuel-derived resins, while containing a biomass-derived raw material; a multilayer structure in which the gas barrier resin is used; and a method for producing such a gas barrier resin composition. The gas barrier resin composition contains at least one type of saponified ethylene-vinyl ester copolymer, wherein of ethylene and a vinyl ester, which are raw materials of the at least one type of saponified ethylene-vinyl ester copolymer, a part is derived from biomass, and a remainder is derived from a fossil fuel.

First claim

The invention claimed is:

1 . A gas barrier resin composition comprising at least one type of saponified ethylene-vinyl ester copolymer, wherein
of ethylene and a vinyl ester, which are raw materials of the at least one type of saponified ethylene-vinyl ester copolymer, a part is derived from biomass, and a remainder is derived from a fossil fuel.

2 . The gas barrier resin composition according to claim 1 , wherein
the at least one type of saponified ethylene-vinyl ester copolymer comprises:
a saponified ethylene-vinyl ester copolymer (A) in which of ethylene and a vinyl ester, which are raw materials thereof, at least a part is derived from biomass; and
a saponified ethylene-vinyl ester copolymer (B) which is derived from a fossil fuel.

3 . The gas barrier resin composition according to claim 2 , wherein a mass ratio (A/B) of the saponified ethylene-vinyl ester copolymer (A) to the saponified ethylene-vinyl ester copolymer (B) is 1/99 or more and 99/1 or less.

4 . The gas barrier resin composition according to claim 1 , wherein the at least one type of saponified ethylene-vinyl ester copolymer comprises an ethylene-vinyl alcohol copolymer (A′) in which of ethylene and a vinyl ester, which are raw materials thereof, a part is derived from biomass, and
a remainder is derived from a fossil fuel.

5 . The gas barrier resin composition according to claim 1 , wherein a biobased content of the at least one type of saponified ethylene-vinyl ester copolymer is 1% or more and 99% or less.

6 . The gas barrier resin composition according to claim 1 , having a biobased content of 1% or more and 99% or less.

7 . The gas barrier resin composition according to claim 1 , comprising a sulfur compound at a concentration of more than 0 ppm and 100 ppm or less in terms of sulfur atoms.

8 . The gas barrier resin composition according to claim 7 , wherein the sulfur compound is dimethylsulfide or dimethylsulfoxide.

9 . The gas barrier resin composition according to claim 1 , wherein of the raw materials, at least a part of the ethylene is derived from biomass.

10 . The gas barrier resin composition according to claim 1 , wherein of the raw materials, at least a part of the vinyl ester is derived from biomass.

11 . The gas barrier resin composition according to claim 1 , wherein the at least one type of saponified ethylene-vinyl ester copolymer comprises a modifying group represented by the following general formula (I):

wherein, in the general formula (1), X represents a hydrogen atom, a methyl group, or a group represented by R 2 -OH; and R 1 and R 2 each independently represent a single bond, an alkylene group having 1 to 9 carbon atoms, or an alkyleneoxy group having 1 to 9 carbon atoms, wherein the alkylene group and the alkyleneoxy group may comprise a hydroxyl group, an alkoxy group, or a halogen atom.

12 . The gas barrier resin composition according to claim 1 , comprising carboxylic acid at a concentration of 30 ppm or more and 1,000 ppm or less in terms of carboxylic acid radical equivalent.

13 . The gas barrier resin composition according to claim 1 , comprising a metal ion at a concentration of 1 ppm or more and 1,000 ppm or less.

14 . The gas barrier resin composition according to claim 1 , comprising a phosphate compound at a concentration of 1 ppm or more and 200 ppm or less in terms of phosphorus atoms.

15 . The gas barrier resin composition according to claim 1 , comprising a boron compound at a concentration of 5 ppm or more and 5,000 ppm or less in terms of boron atoms.

16 . The gas barrier resin composition according to claim 1 , wherein the at least one type of saponified ethylene-vinyl ester copolymer comprises:
a saponified ethylene-vinyl ester copolymer (X); and a saponified ethylene-vinyl ester copolymer (Y) having a melting point which is lower than a melting point of the saponified ethylene-vinyl ester copolymer (X).

17 . The gas barrier resin composition according to claim 1 , further comprising an inorganic particle (C), wherein
a content of the inorganic particle (C) is 50 ppm or more and 5,000 ppm or less.

18 . The gas barrier resin composition according to claim 1 , further comprising an antioxidant (D), wherein
a content of the antioxidant (D) is 0.01% by mass or more and 5% by mass or less.

19 . The gas barrier resin composition according to claim 1 , further comprising:
a polyamide (E); and at least one type of a metal atom (F) selected from the group consisting of atoms of magnesium, calcium, and zinc, wherein a mass ratio of the polyamide (E) to the at least one type of saponified ethylene-vinyl ester copolymer is 5/95 or more and 40/60 or less, and a content of the metal atom (F) is 1 ppm or more and 500 ppm or less.

20 . The gas barrier resin composition according to claim 1 , further comprising a thermoplastic elastomer (G), wherein
a mass ratio of the thermoplastic elastomer (G) to the at least one type of saponified ethylene-vinyl ester copolymer is 5/95 or more and 35/65 or less.

21 . A method for producing a gas barrier resin composition, wherein
the method comprises a step of dry-blending pellets of a saponified ethylene-vinyl ester copolymer (A) with pellets of a saponified ethylene-vinyl ester copolymer (B) and carrying out melt kneading, of ethylene and a vinyl ester, which are raw materials of the saponified ethylene-vinyl ester copolymer (A), at least a part is derived from biomass, and the saponified ethylene-vinyl ester copolymer (B) is derived from a fossil fuel.

22 . A method for producing the gas barrier resin composition according to claim 19 , comprising a step of mixing: pellets of the at least one type of saponified ethylene-vinyl ester copolymer; pellets of the polyamide (E); and a compound comprising at least one type of the metal atom (F) selected from the group consisting of atoms of magnesium, calcium, and zinc, and carrying out melt kneading.

23 . A method for producing a gas barrier resin composition, wherein
the method comprises a step of dry-blending pellets of a saponified ethylene-vinyl ester copolymer (A), pellets of a saponified ethylene-vinyl ester copolymer (B), and pellets of a thermoplastic elastomer (G), and carrying out melt kneading, of ethylene and a vinyl ester, which are raw materials of the saponified ethylene-vinyl ester copolymer (A), at least a part is derived from biomass, and the saponified ethylene-vinyl ester copolymer (B) is derived from a fossil fuel.

24 . A molded product comprising a gas barrier layer formed from the gas barrier resin composition according to claim 1 .

25 . A film or sheet comprising the molded product according to claim 24 .

26 . An industrial film or industrial sheet comprising the molded product according to claim 24 .

27 . A thermoformed container comprising the molded product according to claim 24 .

28 . A blow-molded container comprising the molded product according to claim 24 .

29 . A fuel container comprising the blow-molded container according to claim 28 .

30 . A bottle-shaped container comprising the blow-molded container according to claim 28 .

31 . A tube comprising the molded product according

Assignees

• Kuraray Co

Inventors

• Nakaya Masakazu
• Oshita Mizuko

Classifications

• F16L9/12

  of plastics with or without reinforcement (F16L9/16 - F16L9/22 take precedence) · CPC title

• C08L2207/04

  Thermoplastic elastomer · CPC title

• C08L2205/035

  containing four or more polymers in a blend · CPC title

• C08L2205/025

  containing two or more polymers of the same hierarchy C08L, and differing only in parameters such as density, comonomer content, molecular weight, structure · CPC title

• C08L2203/18

  used for pipes · CPC title