Preparation and Copolymerization of Methacrylate-Terminated Ionic Liquid Rubbers

Preparation of methacrylate-terminated ionic liquid rubbers (MTILR) was investigated by the addition reaction of partially neutralized carboxyl-terminated liquid rubbers (PNCTLR) with glycidyl methacrylate. The PNCTLR were prepared from a polymer of butadiene (BD) (Hycar CTB 2000X162) and a copolymer of BD-acrylonitrile (Hycar CTBN 1300X8) by partial neutralization with MgO and CaO. The metal carboxylate groups of PNCTLR catalyzed the reaction. The Mg carboxylate group showed higher catalytic activities than the Ca carboxylate group. The MTILR obtained were copolymerized with styrene. The novel ionic copolymers obtained were evaluated for their physical properties. The copolymers containing Mg showed better physical properties than their reference copolymers not containing ionic links, an effect of introducing metal. The Ca-containing copolymers showed poor physical properties, probably due to lower interionic attraction of Ca2+, to heterogeneity of the systems, and to lower overall cross-linking densities. Resistance to water and chemical attack, thermal behavior, and stress relaxation are also discussed.