RAFT Polymerization of MMA in the Channels of Different Mesoporous Materials

Abstract

A serial of mesoporous materials (MS), i.e., rod-liked and spherical SBA-15, spherical MCM-41 and MCM-48 were successfully synthesized and modified by silane coupling agent KH550 then utilized as a microreactor for reversible addition–fragmentation chain transfer (RAFT) polymerization of methyl methacrylate (MMA) using a xanthate as a chain transfer agent and AIBN as an initiator. The structures, morphologies and properties of the obtained polymers and composites were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, nitrogen adsorption and desorption, thermogravimetry analysis, gel permeation chromatograph, and hydrogen nuclear magnetic resonance. Results showed that compared with conventional MS, modified MS featured with lower specific surface area and pore volume while maintained the original morphological structure. Owing to confinement effects, PMMAs obtained from internal mesoporous channels featured with higher molecule weight and initial thermal decomposition temperature than these from conventional RAFT polymerization, especially, the PMMA obtained from the spherical SBA-15 and modified MCM-48 exhibited the highest molecule weight.