Reduction of Volatile Organic Compound Emission. II.Use of Alkoxy-Modified Silsesquioxane for Compounding Silica-Filled Rubbers

摘要

A class of alkoxy-modified silsesquioxane(AMS) containing less than 5 wt % of latent alcohol thatcan be used for compounding silica-filled rubbers isdescribed. The AMS derived from octyl-triethoxysilane(OTES) behaves as a good shielding agent in silica-filledrubber to significantly reduce the compound Mooney vis-cosity and filler flocculation. The co-AMS prepared fromOTES and 3-mercaptopropyl-trimethoxysilane yielded aneffective shielding and coupling agent for reinforcing thesilica-filled vulcanizates. The alcohols released as volatileorganic compounds (VOC) are quantified during com-pounding and processing along with the compound prop-erties of silica-filled vulcanizates containing various siliconcompounds such as bis-(triethoxysilyl propyl) disulfide(TESPD), a polyhedral oligomeric silsesquioxanes (POSS),OTES, AMS, or co-AMS. Dynamic mechanical properties such as dependences of hysteresis on temperature (HTD)and storage modulus on strain (MSD) are discussed. Stron-ger HTD and weaker MSD were found in stocks contain-ing co-AMS or a combination of AMS and a couplingagent when compared with that with TESPD. StrongerHTD and weaker MSD may benefit a tire compound withlower rolling resistance, more stable handling perform-ance, as well as better wet traction. More importantly, theVOC released during the manufacture of rubber articlesare significantly reduced in stocks containing AMS (orco-AMS) when compared with those with a silane.