Preparation and optical properties of titania/epoxy nanocomposite coatings

This work reports the preparation of TiO₂/Epoxy nanocomposites coatings with high refractive index and optical transparency. Highly dispersed titania nanoparticles were synthesized by sol-gel method at room temperature. The TiO₂ nanoparticles can be dispersed directly into the polymer without the use of organic surfactant. Nanocomposite coating with refractive index of 1.668 can be obtained by adding 30 wt% TiO₂ nanoparticles into the polymer matrix. All coatings with different amount of TiO₂ exhibit excellent optical transparency of more than 90%. Although higher refractive index of the nanocomposite can be obtained by increasing the content of TiO₂ nanoparticles, cracks also appear in the surface of the hybrid coating.