Thermal Stability Analysis of PbO/ISO-UP Resin Composites

Composites of isophthalate-based unsaturated polyester (ISO-UP) resin with various concentrations of lead monoxide (PbO) filler were fabricated and investigated for degradation kinetics & thermal stability of the composites. The thermogravimetric data have been treated with Freeman-Caroll & Horowitz-Metzger methods, and results were discussed. The filler concentration effect on thermal stability & degradation kinetics of composites were also discussed. The neat sample was observed to exhibit one-stage degradation, while the filled composites underwent degradation at two stages. Further, with the increased filler content in the composite, the initial degradation temperature values (IDT) were found to decrease from 3370C for the neat polymer to 3040C for 50% filled composite, whereas the presence of filler slows down the degradation process. Among the two classical degradation kinetic theories used, the Freeman-Caroll method yields almost close activation energies from 18.295KJ/mol to 20.029KJ/mol, while the Horowitz-Metzger method yields activation energies from 17.919KJ/mol to 13.198KJ/mol.