Incorporation of titanium dioxide particles into polymer matrix using block copolymer micelles for fabrication of high refractive and transparent organic–inorganic hybrid materials

Abstract

Abstract We report a novel strategy for incorporation of titanium dioxide (TiO 2 ) particles into poly(methyl methacrylate) (PMMA) to exploit high refractive and transparent organic–inorganic hybrid materials. Formation of TiO 2 particles of around 20 nm was conducted within hydrophilic core of block copolymer micelles of poly(methyl methacrylate‐ block ‐acrylic acid) (PMMA‐ b ‐PAA) in toluene via sol–gel process from titanium isopropoxide and hydrochloric acid. Subsequently, incorporation of TiO 2 particles into PMMA matrix was carried out by casting toluene solution of TiO 2 precursor‐loaded copolymer micelles, prepared from PMMA 350 ‐ b ‐PAA 93 and the precursor of mole ratio Ti 4+ /carboxyl 4.0, and PMMA. Hybrid films of TiO 2 /PMMA exhibited high transparency to achieve transmission over 87% at 500 nm at 30 wt % of TiO 2 content. The refractive index of resulting hybrid films at 633 nm linearly increased with TiO 2 content to attain 1.579 at 30 wt % TiO 2 , which was 0.1 higher than that of PMMA. Cross‐sectional transmission electron microscope images of TiO 2 /PMMA hybrid films showed existence of TiO 2 clusters less than 100 nm, which were probably formed by aggregation or agglutination of TiO 2 particles during a drying process. It was also observed that decomposition temperature of the hybrid films elevated with increasing TiO 2 content. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011