In-chain multi-functionalized polystyrene by living anionic copolymerization with 1,1-bis(4-dimethylaminophenyl)ethylene: Synthesis and effect on the dispersity of carbon black in polymer-based composites

In-chain multi-functionalized polystyrene possessing definite geminal dimethylamino groups along the polymer backbone, poly(styrene-co-1,1-bis(4-dimethylaminophenyl)ethylene) (poly(styrene-co-BDADPE)), has been designed and synthesized via living anionic copolymerization of styrene with 1,1-bis(4-dimethylanimophenyl)ethylene in benzene at 50 °C, using sec-butyllithium as initiator. The amine functionality was readily controlled by the monomer feed ratio and molecular weight. Compositions of styrene/BDADPE were 9.0–57.9 when ratios of styrene/BDADPE = 0.45–7.79 and Mn = 4.7–15.5 kg/mol. The incorporation of 1,1-bis(4-dimethylanimophenyl)ethylene unit resulted in an increase in glass transition temperature of copolymer and was hindered in the presence of Lewis base. The monomer reactivity ratio for styrene, r1 = 53.4, was obtained. Such in-chain multi-functionalized polystyrene significantly improved the dispersity of carbon black in the corresponding composites, as verified by SEM observation. This in-chain multi-functionalization of matrix polymer via anionic copolymerization employing 1,1-bis(4-dimethylaminophenyl)ethylene as comonomer provides a facile and effective method to prepare carbon black-based polymer composites with good dispersity.