| 摘要 |
PURPOSE:A foam of multilayered structure having improved resistance to weather, oils, solvents, etc., by incorporating a copolymer of methyl methacrylate with styrene of specific composition ratio with a polymer of multilayered structure having a hard layer and a soft elastic layer of a specific copolymeric composition as a basic structure. CONSTITUTION:A resin foam prepared by polymerizing 40-60wt% methyl methacrylate with 60-40wt% styrene, incorporating (A) 20-90pts.wt. (A) resultant copolymer with (B) 80-10pts.wt. polymer of multilayered structure, i.e. an alternating polymer of (i) a hard layer, consisting of methyl methacrylate, styrene and 20wt% or less copolymerizable monomer, and having >=25 deg.C Tg and (ii) a soft elastic layer, prepared by polymerizing butadiene, etc. with an alkyl methacrylate and a crosslinking agent, and having <=25 deg.C Tg, and expansion molding the resultant mixture with a blowing agent, e.g. ''Freon ''. |
