The creation of films formed by the incorporation of ZnO or TiO2 in poly(methylmethacrylate) PMMA matrices was proposed in order to improve their properties as resistance to high temperatures. ZnO and TiO2 nanoparticles were synthesized by the sol-gel method, which does not require the use of surfactants and is easily scalable. In the present work, zinc oxide (ZnO) or titanium oxide (TiO2) incorporations were carried out in a polymeric matrix of Poly(methylmethacrylate) PMMA. Both oxides were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction spectroscopy (XRD) and diffuse reflectance UV-Vis spectroscopy. PMMA was obtained by the suspension free radical polymerization method and PMMA composites containing ZnO or TiO2 were obtained. Polymer characterization was performed using Fourier transform infrared spectroscopy (FTIR). The composites were analyzed by thermogravimetric analysis (TGA) and its thermal resistance was found to be the best incorporation of TiO2 in 1%.