Synthesis and Characterization of PMMA/SiO2 Organic-Inorganic Hybrid Materials Via RAFT-Mediated Miniemulsion Polymerization

摘要

In this article, we first carried out the surface modification of SiO2 using silane coupling agent KH570, and then prepared PMMA/SiO2 organic-inorganic hybrid materials by conventional free radical polymerization and RAFT polymerization in miniemulsion, respectively. The kinetics comparisons of these two polymerizations were studied. PMMA/SiO2 hybrid materials were characterized by gel permeation chromatography, differential scanning calorimetry and thermogravimetric analysis. Experimental results indicated that the polymerization behavior of MMA in miniemulsion showed controlled/living radical polymerization characteristics under the control of RAFT agent. Incorporation of RAFT agent and SiO2 nanoparticles improved the thermal properties of polymers, the thermal stability of polymers increased with increasing content of SiO2 nanoparticles. The structures and morphologies of SiO2, modified SiO2, and PMMA/SiO2 hybrid materials were characterized by FT-IR and TEM. TEM results showed that the addition of modified SiO2 nanoparticles to miniemulsion polymerization system obtained different morphology latex particles. Most of modified SiO2 nanoparticles were wrapped by polymer matrix after polymerization