LAUSR

This work investigates mechanical properties of styrene-butadiene rubber (SBR) composites incorporating magadiite (MGD), a synthetic layered silicate (Na2Si14O29·9H2O) with surface chemistry similar to precipitated silica used in tire tread formulations. Treatment with cetyltrimethylammonium (CTA+) expands the MGD layers and makes the interlayer face surfaces accessible to sulfur-functional silane TESPT (Si69) and SBR, primarily during batch mixing. DMA and tensile testing of cured CMGD/SBR composites show that CTA-treated MGD (CMGD) provides substantially higher levels of mechanical reinforcement than equivalent amounts of silica. However, CMGD/SBR composites exhibit larger loss tangent values above Tg, probably due to lower SBR-SBR crosslink density resulting from interlayer trapping of sulfur released by Si69 during vulcanization. DMA and tensile testing also demonstrate Si69's critical role in forming MGD-SBR graft sites essential to mechanical reinforcement. Replacing silica with CMGD reduces composite weight without sacrificing tensile modulus, suggesting that use of CMGD in tire rubber formulations could improve vehicle energy efficiency. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 133, 44763.