摘要 |
A foam article is made by (1) irradiating a propylene polymer material selected from the group consisting of (a) a terpolymer of propylene, ethylene, and butene-1, (b) a polyolefin composition that includes (i) about 31% to about 39 % of a copolymer of propylene and ethylene, and (ii) about 58% to about 72% of a terpolymer of propylene, ethylene, and butene-1, and (c) a polyolefin composition that includes (i) about 30% to about 65% of a copolymer of propylene and butene-1, and (ii) about 35% to about 70% of a copolymer of propylene and ethylene, and (2) extruding the irradiated propylene polymer material through a die in the presence of a physical expanding agent and a cell nucleating agent, whereby a structure is formed whose density is at least 10 X less than the initial density of the propylene polymer material. The foam articles exhibit improved flexibility and low temperature toughness compared to conventional propylene polymer materials.
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