用低相对分子质量端羧基液体氟橡胶改性固体氟橡胶

Modification of solid fluoro rubber with low molecular weight carboxyl-terminated liquid fluoro rubber

在固体氟橡胶混炼胶中引入端羧基液体氟橡胶(CTLF),研究了混炼胶的加工性能、硫化物性、力学性能和耐高低温性能。结果表明,当羧基质量分数为2.21%的CTLF在混炼胶中质量分数达到10%时,混炼胶的性能最佳,其拉伸强度和撕裂强度分别达到15.7 MPa和33.5 kN/m。CTLF的增强效应源于羧基与混炼胶中的吸酸剂氧化镁之间的离子相互作用,离子型交联是混炼胶力学性能提高的根本原因。此外,CTLF的引入提高了硫化胶的高温残炭率,且对体系的玻璃化转变温度无影响。

Carboxyl-terminated liquid fluoro rubber(CTLF)was incorporated into solid fluoro rubber,and processing properties,mechanical properties,thermal performance and low temperature properties of the resulting vulcanizate were examined.The results showed that when CTLF with carboxyl mass fraction of 2.21%reached mass fraction of 10%in the vulcanizate,the vulcanizate properties were the best,and the tensile strength and tear strength were improved to be 15.7 MPa and 33.5 kN/m respectively.The reinforcement of CTLF was ascribed to the ionic interaction between carboxyl group and magnesium ion from the acidacceptor,magnesium oxide,and the improvement of mechanical properties resulted from ionic crosslinking.In addition,carbon residue at high temperature increased and glass transition temperature was not affected after the incorporation of CTLF.