Kinetic and Mechanistic Study of Heterogeneous Double Metal Cyanide-Catalyzed Ring-Opening Multibranching Polymerization of Glycidol
Chinh Hoang Tran, Min Woong Lee, Suna Kim, Han Byul Jang, Il Kim
Abstract
Polyglycidols of tunable degree of branching (DB) have been synthesized via ring-opening multibranching polymerization (ROMBP) of glycidol in the absence of any initiators using heterogeneous double metal cyanide (DMC) catalysts. Semi-branched polyglycidols of low DB (less than 0.3) are obtained using simple solvent-free batch polymerizations, whereas hyperbranched analogues of high DB (more than 0.5) are achieved employing semi-batch (or slow monomer addition) polymerizations. The rate of DMC-catalyzed ROMBPs of glycidol shows the first-order dependences on monomer and catalyst concentrations, suggesting that the ROMBPs proceed via a coordinative mechanism. The formation of propagating species and the resultant microstructural units are clarified using a conversion versus time analysis in the NMR-scale.