Homogeneous organic-inorganic hybrid materials with excellent thermal and optical performance were successfully prepared via the mixing of (3-methacrylo-xypropyl)trimethoxysilane-capped acrylic resin with titania synthesized by sol-gel approaches. The effects of the titania content, amount of water, and pH in the sol-gel and the ratio of the solvents (butyl acetate and ethanol) on the structures and properties of the hybrid materials were studied. More titania, more water, and base catalysis in the sol-gel process and a higher ratio of butyl acetate to ethanol for the hybrids led to a larger size and a more compact structure of the titania phase. Increasing the titania content dramatically improved the glass-transition temperature, UV-shielding properties, and refractive index for the hybrid materials, and it did not reduce their optical transparency. In general, better thermal stability and optical properties were achieved for the hybrid materials prepared with less water, lower pH values (e.g., acidic or neutral conditions), and a lower ratio of butyl acetate to ethanol. (C) 2005 Wiley Periodicals, Inc.