| 摘要 |
PURPOSE:To manufacture a crosslinked polypropylene foam having excellent heat-resistance in the form of a long continuous sheet, economically, by foaming a silane-grafted propylene-ethylene block copolymer having a specific structure in the presence of a specific foaming agent and a catalyst. CONSTITUTION:A silane-grafted propylene-ethylene copolymer having an MI of 20-100 [the sea structure (continuous phase) is a propylene-ethylne random copolymer having an ethylene content of 0.5-5wt%, and the island structure (noncontinuous phase) is ethylene component, and the content of the ethylene component in the whole sea and island structure is 1-20%] is mixed with a thermally decomposable foaming agent (e.g. azodicarbonamide) and a silanol condensation catalyst, and formed under a condition to keep the foaming agent from decomposition. Thereafter, the crosslinking structure is introduced into the formed article in the presence of water, and the product is heated at a temperature above the decomposition point of the foaming agent. |
