Effect of molecular weight and its distribution on properties of high trans-1,4-butadiene-isoprene copolymer rubber

The effects of molecular weight(Mooney viscosity)and MWD on the properties of trans1,4-butadiene-isoprene copolymer rubber(TBIR)were investigated.The results showed that,the masticating and mixing behaviors of the raw TBIR were improved when the Mooney viscosity of TBIR reduced,and the mixing and processing became difficult when the Mooney viscosity was higher than 60.The comprehensive physical properties of TBIR were improved as the Mooney viscosity increased,but the physical properties and dynamic properties improved little when the Mooney viscosity was higher than 55.The best comprehensive properties were obtained when the Mooney viscosity was 50～60.The tensile properties,wear resistance and heat build-up of raw TBIR and TBIR vulcanizate with bimodal MWD were better,but the flex fatigue life of TBIR vulcanizate with unimodal MWD was better.