| 摘要 |
PURPOSE:To obtain a foamed polyethylene having excellent thermal and mechanical properties and good weatherability and flexibility, and formable easily, by using a specific polyethylene composed of ethylene and an alpha-olefin. CONSTITUTION:A polyethylene having a melt flow rate of preferably 0.5-20g/ 10min, a density of preferably 0.915-0.935g/cm<3>, and a melting point of preferably 115-127 deg.C, and composed of ethylene and a preferably 5-20C alpha-olefin (e.g. 1-butene) (preferably an ethylene copolymer having a molecular weight distribution of preferably <=6) is mixed with a decomposition-type foaming agent which evolves gas by heating (preferably an azodicarbonamide having a main decomposition point of >=196 deg.C). The mixture is molten and kneaded at a temperature lower than the decomposition point of the foaming agent and molded. The molded article is crosslinked and foamed by heating at or above the decomposition point of the foaming agent to obtain the objective foamed article. |
