Preparation and experimental investigations of the spectroscopic, thermal and microstructural properties of polycarbonate filled with bismuth oxychloride

Abstract

Composite films of polycarbonate (PC), loaded with different amounts of bismuth oxychloride (BiOCl) as filler have been prepared by solution casting technique, with dichloromethane (DCM) as solvent. The filler was dispersed uniformly in the PC matrix, by using ultrasonic dispersion technique, at room temperature. Pure PC film and composite films with filler level (FL) equal to 0.5%, 5%, 10% and 20% (weight percentages) were cast from solution, using a leveled glass substrate, at room temperature. The composite samples (films) were peeled off from the glass substrate after 24 hours. The XRD scan (intensity versus 2θ) of PC shows a broad amorphous profile, as expected from a non-crystalline polymeric film, whereas the XRD spectra of the composite films showed several prominent x-ray diffraction peaks superposed on a broad profile, indicating semi-crystalline nature of the composites, due to BiOCl (filler). The optical (UV-Visible) absorption spectra of PC showed peaks at 307 nm and 349 nm, corresponding to incident (absorbed) photon energies of 4.04 eV and 3.55 eV, respectively, attributed to strong absorption at these energies by chromophores in the chemical structure of PC. The TG curves of BiOCl/PC shows multiple stages of degradation, especially at higher FL. The degradation starts beyond 300°C even for the 20 wt% BiOCl/PC film, indicating that these composite films have good thermal stability. DSC reveals a glass transition temperature whose value varies from 140°C up to 146°C with change in FL of the composite, indicating a upper working temperature of 125°C − 130°C.