Poly(Styrene-R-Butadiene)-B-Poly(Poly(Ethylene Glycol) Methyl Ether Methacrylate) As A Silica Dispersant In Rubber Compounds

To improve the dispersion of silica in silica-filled styrene-butadiene rubber tire tread compounds, we synthesized poly(styrene-r-butadiene)-b-poly(poly(ethylene glycol) methyl ether methacrylate) (p(SB-b-PEGMA)) as a silica dispersant. p(SB-b-PEGMA) was synthesized by combining living anionic polymerization (LAP) and atom transfer radical polymerization (ATRP). Initially, alpha-bromoisobutyryl-terminated poly(styrene-r-butadiene) (pSB-Br) was prepared by LAP of styrene and butadiene and sequential additions of ethylene oxide and alpha-bromoisobutyryl bromide. pSB-Br was then used as the macroinitiator in the ATRP of PEGMA (M-n = 300 g mol(-1)). The structure of p(SB-b-PEGMA) was characterized using gel permeation chromatography and H-1 NMR spectroscopy. The application of p(SB-b-PEGMA) as a silica dispersant in styrene-butadiene rubber/silica decreased the optimal vulcanization time and improved the mechanical properties, which included 100% and 300% moduli, crosslinking density and silica dispersion. (c) 2013 Society of Chemical Industry