| abstract |
PURPOSE: To obtain the titled foam having a uniform fine cell structure, being excellent in flexibility, elastic recovery and appearance and suited for food containers, by expansion-extruding a specified molten polyester resin mixture. n CONSTITUTION: A molten polyester resin mixture comprising 100pts.wt. mixture of 10W90wt% polyalkylene terephthalate (e.g., polyethylene terephthalate) of an intrinsic viscosity ≥0.5 (in o-chlorophenol at 35°C) and 90W10wt% polyether ester elastomer comprising a polyoxyalkylene glycol in which at least 60mol% of the hard segments comprise polyalkylene terephthalate and the soft segments comprise 20W80wt% polyoxyalkylene glycol of a number-average MW of 300W6,000, 0.1W3pts.wt. epoxy compound having at lest one epoxy group in the molecule (e.g, soybean oil epoxy), 0.05W3pts.wt. substance (e.g., Li 2 ) selected from among group IWIII A metals of the periodic table or their compounds and 1W60pts.wt. blowing agent (e.g, CO 2 ) having an atmospheric b.p. ≥150°C is expansion-extruded. n COPYRIGHT: (C)1987,JPO&Japio |