The composite hydrogels of poly(N-isopropylacrylamide) with nano-TiO₂ were pre-pared by the coupling copolymerization between N-isopropylacrylamide and the nano-TiO₂ particles pre-treated with a silane coupling agent. The N,N'-methylene bisacrylamide was used as the crosslinking agent. The morphology, optical and mechanical properties of the composite hydrogels were studied by SEM, UV-VIS, FT-IR, and dynamic mechanical analysis (DMA) methods, respectively. The results show that the composite hydrogels had a good absorption of UV and their mechanical strength and toughness were improved markedly.

Key words: nano-TiO₂, poly(N-isopropylacrylamide), composite hydrogel, UV absorption, mechanical property