Resin composition

• US 5,346,950 A
• Filed: 10/25/1993
• Issued: 09/13/1994
• Est. Priority Date: 10/14/1988
• Status: Expired due to Term

• Current Assignee: Idemitsu Petrochemical Co., Ltd. (Idemitsu Kosan Company Limited), Kuraray Company Limited
• Original Assignee: Idemitsu Petrochemical Co., Ltd. (Idemitsu Kosan Company Limited), Kuraray Company Limited
• Inventors: Nagata, Shiro, Mochizuki, Akira, Funaki, Keisuke, Sumitomo, Takashi, Negi, Taichi, Yamasaki, Komei
• Primary Examiner(s): Seidleck, James J.
• Assistant Examiner(s): Clark, W. Robinson H.
• Application Number:
  US08/140,886
• Time in Patent Office: 323 Days
• Field of Search: 525/57, 525/241, 525/56
• US Class Current: 525/57
• CPC Class Codes: B32B 2038/0028 Stretching, elongating
• CPC Class Codes: B32B 2307/306 Resistant to heat
• CPC Class Codes: B32B 2307/7242 Non-permeable
• CPC Class Codes: B32B 2325/00 Polymers of vinyl-aromatic compounds, e.g. polystyrene
• CPC Class Codes: B32B 2331/04 Polymers of vinyl acetate, e.g. PVA
• CPC Class Codes: B32B 27/08 of synthetic resin
• CPC Class Codes: B32B 27/18 characterised by the use of special additives
• CPC Class Codes: B32B 27/302 comprising aromatic vinyl (co)polymers, e.g. styrenic (co)polymers
• CPC Class Codes: B32B 27/306 comprising vinyl acetate or vinyl alcohol (co)polymers
• CPC Class Codes: B32B 37/153 at least one layer is extruded and immediately laminated while in semi-molten state
• CPC Class Codes: B32B 7/12 using interposed adhesives or interposed materials with bonding properties
• CPC Class Codes: C08L 23/28 by reaction with halogens or compounds containing halogen C08L23/32 takes precedence
• CPC Class Codes: C08L 25/06 Polystyrene
• CPC Class Codes: C08L 2666/04 Macromolecular compounds according to groups C08L7/00 - C08L49/00, or C08L55/00 - C08L57/00; Derivatives thereof
• CPC Class Codes: C08L 29/04 Polyvinyl alcohol; Partially hydrolysed homopolymers or copolymers of esters of unsaturated alcohols with saturated carboxylic acids
• CPC Class Codes: Y10S 264/33 Blow-molding articles of nonuniform thickness
• CPC Class Codes: Y10S 428/91 Product with molecular orientation
• CPC Class Codes: Y10T 428/1341 Contains vapor or gas barrier, polymer derived from vinyl chloride or vinylidene chloride, or polymer containing a vinyl alcohol unit
• CPC Class Codes: Y10T 428/1383 Vapor or gas barrier, polymer derived from vinyl chloride or vinylidene chloride, or polymer containing a vinyl alcohol unit is sandwiched between layers [continuous layer]
• CPC Class Codes: Y10T 428/31507 Of polycarbonate
• CPC Class Codes: Y10T 428/3175 : Next to addition polymer from unsaturated monomer[s]
• CPC Class Codes: Y10T 428/31757 : Polymer of monoethylenically unsaturated hydrocarbon
• CPC Class Codes: Y10T 428/31797 : Next to addition polymer from unsaturated monomers
• CPC Class Codes: Y10T 428/3192 : Next to vinyl or vinylidene chloride polymer

Abstract

A resin composition comprising 5 to 95 parts by weight of a saponified product of an ethylene-vinyl acetate copolymer (A) having an ethylene content of 20 to 60 mol % and a degree of saponification of at least 90% and 95 to 5 parts by weight of a styrene-based polymer (B) having mainly syndiotactic configuration. The resin composition has gas barrier properties and a markedly improved heat resistance.

Claims

1. A resin composition comprising a blend of 5 to 95 parts by weight of (A) a saponified product of an ethylene-vinyl acetate copolymer having an ethylene content of 20 to 60 mol % and a degree of saponification of at least 90% and 95 to 5 parts by weight of (B) a styrene-based polymer having mainly syndiotactic configuration.

2. The resin composition of claim 1, wherein the saponified product of the ethylene-vinyl acetate copolymer has an ethylene content of 25 to 50 mol %, a degree of saponification of at least 95% and a melt index of 0.1 to 50 g/10 minutes.

3. The resin composition of claim 2, wherein (B) is a styrene-based polymer having a syndiotactic configuration such that the proportion of structural units continuously connected to each other in a racemic pentad is at least 35%, said styrene-based polymer is a polymer selected from the group consisting of polystyrene, poly(alkylstyrene), poly(halogenated styrene), poly(alkoxystyrene), poly(vinylbenzoate), and mixtures thereof.

4. The resin composition of claim 2, wherein (B) is a styrene-based polymer selected from the group consisting of polystyrene, polymethylstyrene, polyethylstyrene, polyisopropylstyrene, poly(tert-butylstyrene), polychlorostyrene, polybromostyrene, polymethoxystyrene, polyethoxystyrene and a copolymer of styrene and paramethylstyrene and said styrene-based polymer has a weight average molecular weight of at least 10,000.

5. The resin composition of claim 3, wherein the weight ratio of (A) to (B) is 7:

93 to 70;

30, the styrene-based polymer has a crystallinity of at least 35% and a weight average molecular weight of 50,000 to 3,000,000 and the ethylene-vinyl acetate copolymer has an ethylene content of 25 to 50 mol %, a degree of saponification of at least 95% and a melt index of 0.5 to 20 g/10 minutes.

6. The resin composition of claim 3, wherein the saponified product of the ethylene-vinyl acetate copolymer has an ethylene content of 32 mol %, a degree of saponification of 99.4% and a melt index of 1.3 g/10 minutes;

the styrene-based polymer has a syndiotactic configuration such that the proportion in a racemic pentad is 96% and the styrene-based polymer has a melting point of 268°

C.

7. The resin composition of claim 5, wherein said styrene-based polymer is syndiotactic polystyrene.

8. The resin composition of claim 6, wherein said styrene-based polymer is syndiotactic polystyrene.

9. The resin composition of claim 1, wherein the ethylene-vinyl acetate copolymer has an ethylene content of 32 mol % and a degree of saponification of 99.4%.

10. The resin composition of claim 1, wherein a 20 μ

m film of said resin composition has an oxygen permeation speed PO₂ of 0.3-150 cc.20 μ

m/m².day.atm.

11. The resin composition of claim 10, wherein said oxygen permeation speed PO₂ is 0.3-1.9 cc.20 μ

m/m².day.atm.