Resin composition and molded article obtained using this resin composition

Patent metadata

Field	Value
Publication number	US-12428555-B2
Application number	US-202017423217-A
Country	US
Kind code	B2
Filing date	Jan 20, 2020
Priority date	Jan 23, 2019
Publication date	Sep 30, 2025
Grant date	Sep 30, 2025

Abstract

This invention has an object to provide: a resin composition excellent in impact resistance, flexibility, and recyclability obtained as a result of blending a specific ethylene-vinyl acetate copolymer composition with a brittle resin, a recycled resin, or a composite resin including two or more kinds of different resins mixed therein; and a molded article produced with use of the resin composition. The resin composition includes: a thermoplastic resin (A) in an amount of not less than 1 weight % and not more than 99 weight %; and an ethylene-vinyl acetate copolymer composition (B) in an amount of not less than 1 weight % and not more than 99 weight %, the ethylene-vinyl acetate copolymer composition (B) including two or more kinds of ethylene-vinyl acetate copolymers having different vinyl acetate contents, the total amount of (A) and (B) being 100 weight %.

First claim

The invention claimed is:

1. A resin composition comprising:
a thermoplastic resin (A) in an amount of not less than 1 weight % and not more than 99 weight %; and
an ethylene-vinyl acetate copolymer composition (B) in an amount of not less than 1 weight % and not more than 99 weight %, the ethylene-vinyl acetate copolymer composition (B) including two or more kinds of ethylene-vinyl acetate copolymers having different vinyl acetate contents,
a total amount of (A) and (B) being 100 weight %,
wherein the two or more kinds of ethylene-vinyl acetate copolymers having different vinyl acetate contents include two or more of the following ethylene-vinyl acetate copolymers:
an ethylene-vinyl acetate copolymer having a vinyl acetate content of not less than 15 weight % and not more than 30 weight %,
an ethylene-vinyl acetate copolymer having a vinyl acetate content of not less than 45 weight % and not more than 55 weight %, or
an ethylene-vinyl acetate copolymer having a vinyl acetate content of not less than 75 weight % and not more than 85 weight %, and
wherein in a case where a difference in vinyl acetate content is taken between the copolymers in the ethylene-vinyl acetate copolymer composition (B), a difference in vinyl acetate content between copolymers of at least one pair among the copolymers in the ethylene-vinyl acetate copolymer composition (B) is not more than 40 weight %.

2. The resin composition as set forth in claim 1 , wherein the ethylene-vinyl acetate copolymer composition (B) includes three or more kinds of ethylene-vinyl acetate copolymers having different vinyl acetate contents.

3. The resin composition as set forth in claim 1 , wherein in a case where a difference in vinyl acetate content is taken between the copolymers in the ethylene-vinyl acetate copolymer composition (B), a difference in vinyl acetate content between copolymers of every pair among the copolymers in the ethylene-vinyl acetate copolymer composition (B) is not more than 70 weight %.

4. The resin composition as set forth in claim 1 , wherein the ethylene-vinyl acetate copolymer composition (B) is crosslinked.

5. The resin composition as set forth in claim 1 , wherein the ethylene-vinyl acetate copolymer composition (B) is a hydrolysate.

6. The resin composition as set forth in claim 1 , wherein the thermoplastic resin (A) contains at least one kind selected from the group consisting of polyolefin, polyester, an acrylic resin, polyamide, polycarbonate, polystyrene, and a styrene-acrylonitrile copolymer.

7. The resin composition as set forth in claim 1 , wherein
the thermoplastic resin (A) is at least one kind selected from the group consisting of high-density polyethylene, low-density polyethylene, linear low-density polyethylene, polypropylene, an ethylene-propylene copolymer, an ethylene-vinyl alcohol copolymer, nylon 6, nylon 6,6, nylon 11, nylon 12, polyethylene terephthalate, a glycol-modified polyethylene terephthalate resin, polybutylene terephthalate, polylactic acids, a copolymer of L-lactic acid and D-lactic acid, and a stereo complex of poly-L-lactic acid and poly-D-lactic acid, and polybutylene succinate.

8. The resin composition as set forth in claim 7 , wherein the thermoplastic resin (A) is at least one kind selected from the group consisting of polylactic acids, a copolymer of L-lactic acid and D-lactic acid, and a stereo complex of poly-L-lactic acid and poly-D-lactic acid, and polybutylene succinate.

9. The resin composition as set forth in claim 7 , wherein
the thermoplastic resin (A) is at least one kind selected from the group consisting of high-density polyethylene, low-density polyethylene, linear low-density polyethylene, polypropylene, an ethylene-propylene copolymer, an ethylene-vinyl alcohol copolymer, nylon 6, nylon 6,6, nylon 11, nylon 12, polyethylene terephthalate, a glycol-modified polyethylene terephthalate resin, and polybutylene terephthalate.

10. A method for producing the resin composition recited in claim 1 , said method comprising the step of:
kneading the thermoplastic resin (A) and the ethylene-vinyl acetate copolymer composition (B) with a twin-screw extruder.

11. The method as set forth in claim 10 , wherein
in the step of kneading the thermoplastic resin (A) and the ethylene-vinyl acetate copolymer composition (B) with the twin-screw extruder, the twin-screw extruder operates at a screw speed of not lower than 50 rpm and not higher than 3000 rpm.

12. A resin composition obtained by the method recited in claim 11 .

13. A molded product obtained by molding the resin composition recited in claim 1 .

14. The resin composition according to claim 1 , consisting of:
the thermoplastic resin (A); and
the ethylene-vinyl acetate copolymer composition (B).

15. The resin composition according to claim 1 , wherein
the thermoplastic resin (A) in an amount of not less than 50 weight % and not more than 90 weight %; and
the ethylene-vinyl acetate copolymer composition (B) in an amount of not less than 10 weight % and not more than 50 weight %.

Assignees

• Tosoh Corp

Inventors

• KUGIMOTO Daisuke
• Kawato Daisuke
• Kouda Shingo

Classifications

• Y02W30/62

  Plastics recycling; Rubber recycling · CPC title

• C08L2205/035

  containing four or more polymers in a blend · CPC title

• C08L2205/03

  containing three 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

• C08L33/12

  Homopolymers or copolymers of methyl methacrylate · CPC title