| 摘要 |
PURPOSE:To provide the foamable resin compsn. which can be easily polymerized without impairing foamability and moldability and without causing carbon defects and flow mark defects at the time of casting by impregnating a copolymer of a specific compsn. with pentane at a specific ratio. CONSTITUTION:This resin compsn. is produced by impregnating the copolymer which is obtd. by compounding 1 to 55wt.% styrene, 98 to 50wt.% alkyl eater methacrylate having 1 to 4C and 1 to 49wt.% polymerizable monomer expressed by formula ao as to make the entire part 100wt.% and copolymerizing the compsn. and has 50000 to 350000 weight average mol.wt. with the pentane at 0.5 to 10wt.%., where in the formula, R1 is hydrogen or methyl group; R2 is a bivalent org. acid; R3 is 6 to 20C hydrocarbon group; (n) is 0 or 1. Such a resin compsn. has favorable foaming performance and excellent shrinkage resistance of primarily foamed particles and foamed moldings. |
