Preparation of bis-epoxy end capped macromonomers through anionic or RAFT polymerization

The focus of this paper is to report the quantitative synthesis of bis-epoxy end functionalized polyisoprene (BETPI) macromonomers by anionic polymerization and reversible addition fragmentation chain transfer (RAFT) polymerization. For anionic polymerization, more stable and sterically hindered living anions polyisoprene (Li + -PIp-Li + ) react with epichlorohydrin (ECH) for the synthesis of well-defined BETPI. For the high-pressure RAFT polymerization, a novel bis-epoxy end functionalized trithiocarbonate (BODAAT) is designed as RAFT agent for the polymerization of isoprene monomer to obtain well-defined BETPI. The functionalities of the resulting BETPI are analyzed by Fourier transform infrared spectroscopy (FT-IR), NMR, and size exclusion chromatography (SEC). Through two polymerization methods, the BETPI with 600–1000 Da of molecular weight and over 75% of epoxy end capping rate is obtained, which can be further utilized as highly reactive liquid macromonomers.