Patent ID: 6790870
Filing Date: 2004-09-14
Classification: B29C,B29K,C08J

Abstract:
A method of producing a foamed material, said method comprising:contacting a mixture comprising a first thermoplastic polymer and a second thermoplastic polymer with a blowing agent comprising a surfactant, wherein the surfactant is a copolymer selected from the group consisting of a graft copolymer, a block copolymer, and a random copolymer, wherein the first thermoplastic polymer has a higher percent crystallinity that the second thermoplastic polymer; and subjecting the mixture to conditions sufficient to create a thermodynamic instability in the mixture to foam the mixture, the mixture comprising the first and second thermoplastic polymers having a percent crystallinity lower than the first thermoplastic polymer; wherein the foamed material formed by said method has a plurality of distinct void spaces formed therein.