低密度聚乙烯/三元乙丙橡胶热塑性硫化胶的压缩应力弛豫及其可逆回复

摘要

采用动态硫化法制备了低密度聚乙烯(LDPE)/三元乙丙橡胶(EPDM)热塑性硫化胶(TPV),并对其力学性能、微观结构、压缩应力弛豫及其可逆回复进行了研究.结果表明,当LDPE/EPDM质量比为50/50时TPV的综合性能较佳,EPDM硫化胶粒子尺寸为3~5 μm,均匀地分散在刻蚀试样表面.随着LDPE用量的增加或压缩应变的增大,应力弛豫现象趋于显著.随着热处理温度升高或热处理时间的延长,TPV压缩应力弛豫的可逆回复程度提高.%Low density polyethylene(LDPE)/ethylene propylene terpolymer(EPDM) thermoplas-tic vulcanizate(TPV) was prepared by dynamic vulcanization. The mechanical properties, micro-structure, compressive stress relaxation and its re-versibility of TPV were investigated. The results showed that TPV had better comprehensive proper-ties when the mass ratio of LDPE/EPDM was 50/50. And the particle size of EPDM vulcanizate was 3 -5 μm, which was evenly dispersed on the surface of the etching samples. The compressive stress relaxation of TPV increased with increasing amount of LDPE and compression strain. The reversibility of stress relaxation was improved with increasing heat treatment temperature and heat treat-ment time.