| 摘要 |
<p>A foamable and crosslinkable compsn. is prepd. by mixing an olefin homo- and/or co-polymer with a blowing- and a crosslinking agent, and charged to a closed mould. - Novelty comprises: (a) heating the compsn. in the closed mould, under increased pressure, to a temp. causing the crosslinking of the polyolefins, by decomposing the crosslinking agents, without decomposing the blowing agents; (b) the foamable crosslinked prod. obtd. is unmoulded, laid between a pair of metal plates and heated to a foaming temp. by partial decompsn. of the blowing agent. The prod. is expanded biaxially within the zones limited by the metal plates. A pre-foamed intermediate prod. is obtd. having a plate-like structure; (c) the pre-foamed prod. is heated at atmos. pressure, to a temp. corresp. to at least the foaming temp., so as to decompose the residual blowing agent and expand the prod. in all directions.</p> |
