Preparation and characterization of nanostructured TiO2/epoxy polymeric films

Titania-containing coatings were prepared by cationic photopolymerization of an epoxy resin either by dispersion of preformed TiO2 nanoparticles or by their in-situ generation through a sol-gel dual-cure process. The kinetics of photopolymerization was evaluated by real-time FT-IR, studying the effect of the TiO2 concentration. The properties of cured films were investigated, showing an increase of hydrophilicity on the surface of the coatings with increasing TiO2 content. TEM analysis demonstrated that it is possible to achieve a significantly better control of the dispersion of the inorganic particles within the organic matrix by in-situ generation of TiO2, thus completely avoiding macroscopic phase separation and obtaining homogeneous, transparent coatings.