| 摘要 |
PURPOSE:To obtain a foam product having excellent heat resistance by a method in which polyester elastomer is mixed with a blowing agent having a specific decomposing temperature and a multi-functional monomer, and the composition is molded, bridged by radiation, and expanded by heating. CONSTITUTION:Polyster elastomer, or a segmented polyester consisting of a terephthalic acid-based cytstalline polyester hard segment (a) of the formula and an aliphatic polyether soft segment (b) of 600 molecular weights of the formula as an (AB)n type multi-block coplymer, is mixed with a decomposition type blowing agent of a decomposing temperature higher than the melting point (150-230 deg.C) of the polyester elastomer and a multifunctional monomer. The mixture is molded into a sheet by hot press and subjected to irradiation of electron rays. The sheet so treated is then allowed to stand in a constant-temperature tank of 220 deg.C for 5min for expansion to obtain an expanded product of an expansion ratio of 20 times or more. |
