Synthesis and Application of Modified Low MolecularWeight Polyisoprene

Low molecular weight3???4-polyisoprene???LPI???was prepared by anionic solution polymerization and then itwas modified to prepare siloxane modified functionalized low molecular weight3???4-polyisoprene???MLPI??????includingthree end group-modified materials???LPI-propyl methyldimethoxysilane???LPI-CMDS??????LPI-propyl trimethoxysilane???LPI-CTMS??????LPI-propyl trimethoxysilane???LPI-CTES???and one graft-modified material???3-mercaptopropyl triethoxysilane graft modification LPI???LPI-g-MTS???.The influences of LPI and MLPI on dispersion of silica and properties ofsolution polymerized styrene butadiene rubber???SSBR???composites were studied.Improvement of interaction betweenthe filler and the polymer and dispersion of silica in the composites was domenstrated by strain scanning and boundrubber content results.Due to the more active sites???LPI-g-MTS had the best effect.Compared to the unmodified LPIfilled composite???the physical and mechanical properties of the LPI-g-MTS filled composites increased???especially the modulus at300% elongation increased by89.66% and the tensile strength increased by27.15%.This workprovides a new method to improve the dispersion of silica in rubber/silica composites