| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a rubber composition that designs a weight saving, improves permanent strain, besides dispersion in charge during extrusion and shape preserving property, does not reduce characteristics of elongation and stress, etc. and has excellent durability. <P>SOLUTION: This rubber composition is produced by foaming and crosslinking an uncrosslinked rubber composition composed of an ethylene-propylene-nonconjugated polyene copolymer that meets the relationship: Y≤1.1(0.48T-13.19), wherein Y represents a polymer structural index and T (wt%) represents an ethylene content. The foamed and crosslinked rubber composition has hardness of 55(A) or more, is produced by blending the ethylene-propylene-nonconjugated polyene copolymer of Y=20-25 (A) with the ethylene-propylene-nonconjugated polyene copolymer of Y=10-15 (B) in the ratio of (A)/(B)=1-40/99-60 (by wt%), preferably (A)/(B)=1-35/99-65, and has a specific gravity of ≤1.1. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
