Preparation and properties of nanohybrid with polystyrene-grafted-metal oxide nanoparticles

PS-grafted-titanium oxide (diameter 15 nm, TiO₂) and PS-grafted-aluminum hydroxide (diameter 37 nm, Al₂O ₃·xH₂O) nanoparticles were successfully prepared through direct polymerization from immobilized surface initiator that has both phosphoric acid moiety and living radical polymerization moiety. In the case of PS film with non-grafted-TiO₂, the films did not show high light transmittance and ultraviolet absorption characteristic owing to the aggregation of nanoparticles. On the other hand, in the case of PS film with PS-grafted-TiO₂, the films showed high transmittance in the visible light region accompanying ultraviolet absorption characteristic of TiO ₂ due to the fine dispersion of nanoparticles into PS matrix. PS film with PS-grafted-Al₂O₃·xH₂O showed good flame resistance compared with non-grafted-pseudo-boehmite or PS-grafted-boehmite with diameter 240 nm and 110 nm (plate) because of good dispersion in PS matrix and release of structural water during PS degradation.