Compsns. partic. for motor vehicle tyres - comprise diene] rubber, carbon@ black partic. of large specific surface, and copolymer of ethylene@] with vinyl acetate or acrylic acid, for good abrasion resistance, etc.

摘要

Compsns. (I) contain (A) 100 pts. (all pts. wt.) diene rubber (II), (B) 80-200 pts. C black (III), (C) 2-20 pts. ethylene copolymer (IV) contg. 10-20% vinyl acetate or acrylic acid as comonomer and having Brookfield viscosity at 121 deg.C. 500-20,000 mPa.s. Pref. at least 70% (II) is styrene-butadiene rubber (SBR), partic. SBR contg. 30-60% styrene, and partic. proportion of 1,2-bonding in butadiene units is 50-80%. (III) has specific surface (determined by N2 adsorption) at least 120, pref. at least 150 sq.m/g. (I) contain 0.5-2 pts. S and amt. of accelerator such that S:accelerator ratio is 1:5 to 1:10. USE/ADVANTAGE - In prepn. of motor vehicle tyres, partic. tyres for continuous high speed journeys such as racing and long distance lorry tyres, also industrial prods. such as belts and hoses, footwear. Dispersibility of (III) with small particle dia. is improved by (IV) so that reinforcing effect of (III) is fully utilised, tyres have good abrasion-resistance and grip, prods. with consistent properties in which (III) of large surface is uniformly dispersed and having good heat resistance, tyres showing less heat fatigue, are obtd.