Foamed plastics of resin compositions comprising pullulan type resins and thermoplastic resins and process for producing the same
AssigneesSumitomo Chemical Company, Limited, Hayashibara Biochemical Laboratories, Incorporated
InventorsHiroomi Matsunaga, Kozo Tsuji, Teruo Saito
Life of this patent
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Abstract
A foamed plastic of a resin composition comprising a pullulan type resin and a thermoplastic resin. When a resin composition comprising a pullulan type resin and a thermoplastic resin is foamed, the resulting foamed plastic is improved in moisture and water absorptivity which is low in the case of a foamed plastic composed of the thermoplastic resin, and in water resistance which is low in the case of a foamed plastic composed of the pullulan type resin.
Claims15
A foamed plastic of a resin composition comprising 2 to 98% by weight based on the total resin weight of a pullalan type resin having a molecular weight of 10,000 to 5,000,000 selected from the group consisting of pullalan, an etherified pullalan and an esterified pullalan and 98 to 2% by weight based on the total resin weight of at least one thermoplastic resin selected from the group consisting of polyethylene, polypropylene, polystyrene, acrylonitrile-butadiene-styrene copolymer, polymethyl methacrylate, polyvinyl acetate, polyvinyl chloride, polyvinylidene chloride, vinyl acetate-vinyl chloride copolymer, olefin-vinyl acetate copolymers, polycarbonates, polyacetals, polysulfones, polyamides and polyesters.
A process for producing a foamed plastic, characterized in that a resin composition comprising 2 to 98% by weight based on the total resin weight of a pullalan type resin having a molecular weight of 10,000 to 5,000,000 selected from the group consisting of pullalan, an etherified pullalan and an esterified pullalan, 98 to 2% by weight based on the total resin weight of at least one thermoplastic resin selected from the group consisting of polyethylene, polypropylene, polystyrene, acrylonitrile-butadiene-styrene copolymer, polymethyl methacrylate, polyvinyl acetate, polyvinyl chloride, polyvinylidene chloride, vinyl acetate-vinyl chloride copolymer, olefin-vinyl acetate copolymers, polycarbonates, polyacetals, polysulfones, polyamides and polyesters, and 1 to 50% by weight based on the weight of the resin composition of at least one plasticizer for the pullulan type resin selected from the group consisting of water, glycerine, ethylene glycol, polyethylene glycol, sorbitol, propylene glycol, polypropylene glycol, dimethylformamide, triethylenetetramine, diethylenetriamine, ethanolamine, propylamine, propylenediamine, butylamine, ethylamine and dimethylsulfoxide is molded by liberating a vapor of said plasticizer from the resin composition at a temperature above the plasticization temperature and below the decomposition temperature of said resin composition.
A process for producing a foamed plastic, characterized in that a resin composition comprising 2 to 98% by weight based on the total resin weight of a pullalan type resin having a molecular weight of 10,000 to 5,000,000 selected from the group consisting of pullalan, an etherified pullalan and an esterified pullalan, 98 to 2% by weight based on the total resin weight of at least one thermoplastic resin selected from the group consisting of polyethylene, polypropylene, polystyrene, acrylonitrile-butadiene-styrene copolymer, polymethyl methacrylate, polyvinyl acetate, polyvinyl chloride, polyvinylidene chloride, vinyl acetate-vinyl chloride copolymer, olefin-vinyl acetate copolymers, polycarbonates, polyacetals, polysulfones, polyamides and polyesters, 1 to 50% by weight based on the weight of the resin composition of at least one plasticizer for the pullalan type resin selected from the group consisting of water, glycerine, ethylene glycol, polyethylene glycol, sorbitol, propylene glycol, polypropylene glycol, dimethylformamide, triethylenetetramine, diethylenetriamine, ethanolamine, propylamine, propylenediamine, butylamine, ethylamine and dimethyl sulfoxide, and at least one foaming agent selected from the group consisting of solid foaming agents, volatile liquid foaming agents and gaseous foaming agents is molded at a temperature above the plasticization temperature and below the decomposition temperature of said resin composition and at a temperature above the gas-liberating temperature of said foaming agent.
Dependencies are inferred from the claim text.