Facile synthesis of functionalized high vinyl polybutadiene by using 1,2-dipiperidinoethane derivatives as polar modifiers†

Polydiene-based liquid rubber can be used to prepare high-frequency copper-clad plates, and it is also the most critical raw material for photosensitive elastomers used in flexible resin plates. The molecular structure control requirements of high-performance liquid rubber are very high, and special living anionic initiation systems and polymerization processes need to be developed to achieve stable control of the product structure. In this study, a series of novel polar modifiers were synthesized by introducing alkyl substituents and N/O-containing heteroatoms into the cycloamine ring (1,2-dipiperidinoethane (DPE) derivatives). High vinyl polybutadiene (90% < 1,2-units < 99%) with quantitative tertiary-amine functionalization (0%–25% molar ratio) was synthesized by in situ copolymerization using 4-dimethylaminomethylstyrene (VBA) as a comonomer. The polymerization process has obvious characteristics of being controllable and living under mild conditions. The fine structure of the product was analyzed by ¹H NMR, FTIR, GPC, and DSC. In situ anionic copolymerization provides a new way for developing high-performance liquid rubber.