关键词: 有机无机杂化材料, 聚甲基丙烯酸甲酯, 二氧化钛, 溶胶凝胶方法, 热致变色效应

Abstract:

Poly(methyl methacrylate)-titania hybrid glasses were synthesized by sol-gel processes using acrylic acid or allyl acetylacetone as coupling agent. Titanium butoxide modified with acrylic acid (or titanium isopropoxide modified with allyl acetylacetone) was hydrolyzed to produce a titania network, and then poly(methyl methacrylate) (PMMA)chains formed in situ through a radical polymerization were chemically bonded to the forming titania network to synthesize a hybrid glass. Transparent hybrid glasses with different contents of titania were achieved. With the increase of the titania content, the color of the products changed from yellow to red. The synthesis process was investigated stepwise by using FTIR spectroscopies, and the experimental results demonstrated that acrylic or acetylacetonate groups bound to titanium remain in the final hybrid glasses. The thermal stability of the hybrid materials were considerably improved relative to pure PMMA. The hybrid glasses using allyl acetylacetone as coupling agent exhibited thermochromatic effect which both pure PMMA and titania do not manifest.

Key words: Organic-inorganic hybrid materials;Poly(methyl methacrylate)(PMMA);TiO₂;Sol-gel method;Thermochromatic effect