Rubber/Filler Composites Modified By Room Temperature Ionie Liquids

Room temperature ionic liquid (RTIL) was utilized as interfacial modifier for rubber/filler composites with novel interfacial structure and good performance. The affinities of RTIL towards various fillers and their reaction with SBR chains were studied. The influence of RTILs on the microstructure and performance was systemically investigated?RTIL, comprised of an organic cation and an organic or inorganic anion, is molten salt with a molten temperature lower than 100?. For their specific characteristics such as near vapor pressure, high polarity, good thermalstability, wide potential, excellent solubility, high electric and ionic conductivity, RTILs have been widely explored as green solvent, high efficient media, electrolyte and catalysis. RTIL can be interacted with various fillers via the widely reported interactions. So, they can be potentially utilized as interfacial modifiers for polymer/filler composites and greatly improve the performance of the composites.One kind of common RTIL, 1-butyl-3-methylimidazolium hexafluorophosphate rate (BmimPF6) could be interacted with carbon black (CB) via cation-?interaction. Together with microwave irradiation, CB was modified and the structure of CB was found to be substantially changed. BmimPF6 was decomposed on the CB surface. The modified carbon black was found to be with larger surface area, increased graphitization, obviously decreased microcrystalline size and higher content of mesopores. The reinforcement of m-CB towards styrene butadiene rubber (SBR), butadiene rubber (BR) and nitrile butadiene rubber (NBR) was studied. The preparing parameters were optimized. At a low loading of filler, m-CB could more effectively reinforce rubber matrix. While at a high loading of filler, there is no practical difference between m-CB and CB according to the performance of the vulcanizates. The increased interfacial interaction and the higher orientation of the segments in the sticky layer were both responsible.Two kinds of RTILs with polymerizable groups,1-methylimidazolium sorbate (MimS) and 1-methylimidazolium methacrylate (MimMa) were designed and prepared. The performance of the modified SBR/silica composites was characterized and the related mechanism was studied. The incorporation of MimS and MimMa could effectively restrain the filler networking in the rubber matrix, accelerate the vulcanization, obviously improve the dispersion of silica, strengthen the SBR-silica interfacial interaction and largely improve the mechanical performance of SBR/silica vulcanizates.RTIL containing thiol group,1-methylimidazolium propionate (MimMP), was prepared and investigated as interfacial modifier for SBR/silica composites. MimMP could be reacted with SBR chains via the thiol-ene reaction between the thiol group in MimMP and the double bond in SBR chains. The reactive sites in SBR were mainly the side double bonds. MimS and MimMa could be interacted with silica by hydrogen bonding, which could weaken the filler-filler interaction, restrain the filler networking of silica and improve the dispersion of silica in rubber matrix. Thiol and imidazolium cation in MimMP could accelerate the vulcanization. Both the thiol-ene reaction and the hydrogen bonding are responsible for the increased SBR-silica interfacial interaction and the improved mechanical performance of SBR/silica vulcanizates.A kind of RTIL with thiol group and Gemini structure, bis(1-methylimidazolium) mercaptosuccinate (BMimMS), was synthesized. Both MimMP and BMimMS were utilized as interfacial modifiers for SBR/halloysite nanotubes (HNTs) composites. MimMP and BMimMS could be hydrogen bonded with HNTs but with a subtle difference on the mechanism. MimMP could be interacted with the aluminol (A1OH), silanol (SiOH) and aluminum oxide (A1OA1) of HNTs. BMimMS could be interacted with the A1OH, SiOH and silicon oxide (SiOSi). Both MimMP and BMimMS could be grafted onto SBR chains with thiol-ene reaction. MimMP could be mainly reacted with the side double bonds in SBR. While in that of BMimMS, the active sites were almost equally originated from the side double bonds and the inside double bonds possibly due to its Gemini structure. The incorporation of MimMP and BMimMS could effectively accelerate vulcanization, improve the HNTs dispersion, strengthen the SBR-HNTs interfacial bonding and enhance the mechanical performance of the vulcanizates. Because BMimMS could be interacted with the outward surface of HNTs, BMimMS could be more effective in improving the HNTs dispersion, the interfacial bonding and the final performance of the vulcanizates in comparison with that of MimMP.