Abstract
We studied the effects on the properties of processing and vulcanizates of SBR gel which was formed in mastication and the mixing at high temperature. The previous paper reported the much amount of gel content, but this paper showed in the case of small gel amount. Using JSR 1502 as raw polymer, we varied the roll temperature of mastication and filler mixing at 40, 70, 90, 120 and 150°C respectively. The gel content obtained were measured 0.30-0.66% as polymer gel and 14-20% as filler-polymer gel.
The following results were found :
These SBR gel were formed in the roll processing, even if small amount, gave severe influence on Mooney viscosity, mill shrinkage, tackiness of unvulcanizates and increased modulus of vulcanizates, reduced the crack-resistance and swelling in toluene substantially.
