Physical and Optical Properties of Silica/Polymer Nanocomposite Inverse Opal

Silica/polymer nanocomposite inverse opal films were readily fabricated by blending poly(styrene-co-butyl acrylate-co-acrylic acid) latex with colloidal silica particles and subsequent drying at 110 C for 2 h (namely, the “forced-drying” strategy). The structure, mechanical and optical properties, and solvatochromic effect of the inverse opal films were thoroughly examined. SEM and USAXS results indicate that the as-obtained nanocomposite films possess three-dimensionally ordered macropores with fcc structure. DMA and nanoindentation results show that the films possess robust mechanical strength. The films display brilliant monochromatic colors, which can be easily adjusted by the size of the polymer spheres. The position of photonic band gap considerably shifts when the macropores of the films was filled with water, organic solvents or their mixtures. This solvatochromic effect can be used for refractive index sensing and rapid monitoring of the composition of chemical (or biochemical) products.