Effects of different catalysts on the mechanical, thermal, and rheological properties of poly(lactic acid)/polycarbonate blend

Poly(lactic acid)/polycarbonate (PLA/PC) blends are often explored for use in durable applications such as mobile phones, laptops, and automotive parts. With the use of this blend, while reducing the dependence on the petroleum-based polymers, environmental pollution can be prevented. However, PLA/PC blend is immiscible and needs to be compatibilized. To encourage compatibilization and improve of the performance of the PLA/PC blend, TiO2 and CeO2 were incorporated into the blend. The effects of catalysts type and amount on the structural (Fourier transform infrared analysis-FTIR), morphological (scanning electron microscopy-SEM), rheological, mechanical, and thermal properties (thermogravimetric analysis-TGA, differential scanning calorimeter-DSC) of the PLA/PC blends were evaluated in this study. FTIR results revealed that the catalysts promoted the reaction between PLA and PC. The modulus of the blend increased with the addition of catalyst. The CeO2 containing blends exhibited brittle behavior which was also supported by SEM micrographs. The added catalysts acted as a lubricant, lowered the complex viscosity of the blend, and made processing easier. With the addition of fillers at all amounts, thermal decomposition temperature decreased while the residual weight at 800 & DEG;C increased with the inclusion of 3 wt% CeO2. Mechanical results revealed that the highest tensile strength and elongation values were obtained for 0.5 wt% CeO2 and 0.5 wt% TiO2, respectively. It was observed that the loading level and type of catalyst significantly affected the PLA/PC blends mechanical and thermal properties.