CHARACTERIZATION OF TiO_2 FILMS OBTAINED BY SOL-GEL FROM TITANIUM ISOPROPOXIDE IN THE PRESENCE OF HYDROXYPROPYLCELLULOSE

摘要

The fabrication and properties of composite films based on ultrafine TiO_2 particles dispersed in a matrix of thermoplastic polymers, has received a great dedication from many research groups in the last decade. In this work, titanium dioxide porous coatings were produced using sol-gel and spray pyrolysis techniques. The samples were obtained from the hydrolysis and condensation of the precursor reactive titanium isopropoxide Ti[Opr~i]_4 in a mixture of alcoholic-water at room temperature. TiO_2 particles were obtained dispersed in a polymeric matrix of hydroxypropylcellulose (HPC). Surface analysis was carried out using scanning electron microscopy, showing sponge-like morphologies with a large internal surface area. X ray diffraction studies let us detect the presence of titanium oxide in the anatase phase with thermal stability between 400 and 700℃. Substrate behavior did not let us to make studies at higher temperatures. Also Thermogravimetric (TGA), Differential Scanning Calorimetric (DSC), and FTIR measurements were done and the results gave us information about the exact diffusion and decomposition temperature of HPC into the titanium dioxide matrix.