Elastomer compsn. contg. high and low glass transition temp. polymers - for pneumatic tyre tread with good adhesion to wet surfaces

摘要

An elastomer compsn. comprises one or more polymers (I) of low Tg, specifically =-50 degrees C, mixed with a non cross linking polymer (II) or a heavy oil. (I) is pref. natural rubber, (cis-)polybutadiene and/or an SB copolymer. A prefd. (I) comprises a mixt. of 65-85 wt.% natural rubber and 35-15 wt.% SB rubber. Another prefd. (I) comprises 30-40 wt.% natural rubber, 45-55 wt. % polybutadiene and 5-25 wt.% SB copolymer. (II) is pref. an ethylene-propylene rubber present in amt. of 10-40 (15-30) wt.% based on (I). The vulcanised compsn. is partic. for tyre tread and provides excellent adhesion on wet road surface combined with low resistance to friction during rolling.