Abstract
The fractionation of trans-1, 4-poly(butadiene-co-isoprene) copolymer rubbers (TBIR) was carried out by stepwise isothermal crystallization fractionation method. and the structure and composition of the TBIR fractions were studied. It was found that TBIR-20 was a semi-crystalline copolymer with long trans-1, 4- polyisoprene (TPI) blocks and butadiene units randomly distributed in the molecular chain. While TBIR-40 was a copolymer containing TPI blocks and trans-1, 4-polybutadiene (TPB) blocks. The application of TBIR as hump strip stocks in passenger car radical (PCR) tires was investigated. The NR/BR/TBIR compounds showed improved green strength. crystallinity and shore A hardness. as well as accelerated curing rate. For NR/BR/TBIR vulcanizates. physical and mechanical properties. such as tensile strength. tear strength. modulus and resilience stand in a high level. outstanding properties including decreased heat built- up. improved abrasion resistance and ageing- resistant performance. and excellent flexing