In situ sol–gel preparation of high transparent fluorinated polyimide/nano-MgO hybrid films

Hybrid nanocomposite films of magnesium oxide (MgO) in fluorinated polyimide (PI) from 4, 4′-(hexafluoroisopropylidene) diphthalic anhydride (6FDA) and 4, 4′-Diaminodiphenyl ether (ODA) have been successfully fabricated via an in situ sol–gel polymerization technique. The MgO content in hybrid films was varied from 0 to 5 wt%. The hybrid films were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), ultraviolet–visible (UV–Vis) spectroscopy and thermal gravimetric analyses (TGA). The results of FTIR, XRD and FESEM showed that the MgO nanoparticles were well dispersed in the polymer matrix due to the coordination between the carbonyl group of polymers and Mg atom, and the as-prepared hybrid films exhibited excellent optical transparency in the visible region and good UV-shielding properties in the UV region. Although the thermal stability of the hybrid films is slight inferior to pure PI, it is still good for the practical application below the temperature of 300 °C.