COPOLYMER OF 4-METHYL-1-PENTENE AND α-OLEFIN, AND FOAM COMPOSED OF COMPOSITION INCLUDING THE SAME

摘要

PROBLEM TO BE SOLVED: To provide a polyolefin-based resin foam excellent in shock absorbability.SOLUTION: A foam according to the present invention is formed by crosslinking a foam composition which contains a 4-methyl-1-pentene-α-olefin copolymer (A) composed of 20-75 mol% of a constitutional unit (A1) derived from 4-methyl-1-pentene and 80-25 mol% of a constitutional unit (A2) derived from a 2-20C α-olefin other than 4-methyl-1-pentene and has a forming rate of 1.1-50 cc/g. The 4-methyl-1-pentene-α-olefin copolymer (A) has intrinsic viscosity [&eegr;] of 0.01-5.0 dL/g, Mw/Mn of 1.0-3.5, and a maximum tan δ value of 1.0-3.5.