The Effect of Surface Modification of TiO₂ with Diblock Copolymers on the Properties of Epoxy Nanocomposites

摘要

The TiO₂ nanoparticles were modified by diblock copolymers, poly(methyl methacrylate)-b-polystyrene (PMMA-b-PS), via reversible addition-fragmentation chain transfer (RAFT) polymerization, and the epoxy nanocomposites containing different TiO₂ and with different contents were prepared. Subsequently, the effects of TiO₂ content on the mechanical and thermal properties of nanocomposites were investigated. The results indicated that after grafting copolymers onto TiO₂, the dispersion of TiO₂ and interaction with epoxy matrix could be significantly increased, therefore, the mechanical properties of the nanocomposites were improved greatly. When the TiO₂-PMMA-b-PS content was 1Â wt%, the impact strength and flexural strength reached their the best, and increased up to 96% and 43%, respectively. Furthermore, the thermal stability of the nanocomposites was also distinctly improved.