Effect of titanium dioxide particles on the surface morphology and the mechanical properties of PVC composites during QUV accelerated weathering

Abstract

In this study, QUV accelerated weathering of polyvinyl chloride (PVC) composites with different amounts of titanium dioxide (TiO2) particle was conducted to investigate the effect of TiO2 particle on the surface morphology and the mechanical properties. The results indicate that the surface morphology of PVC without TiO2 particle did not exhibit changes up to 960 h, but exhibited a rough and brittle surface after 1920 h of QUV accelerated weathering. In addition, the tan δ intensity, the elongation at break, and the mean failure energy (MFE) decreased significantly with increasing exposure time due to embrittlement. In contrast, for TiO2 particle-loaded PVCs, no significant influence on the tan δ intensity and the mechanical properties after accelerated weathering were observed, despite the appreciable degradation that occurred in the surface layer. The weatherability, as determined by the mechanical performance, was improved with increasing loading of TiO2 particle in the PVC composites. Although the TiO2 particle in the PVC matrix acts as a photocatalyst to enhance the surface degradation, it is also an effective radiation screener that inhibits embrittlement and retards the decrease in mechanical properties caused by the accelerated weathering process. POLYM. COMPOS., 37:3391–3397, 2016. © 2015 Society of Plastics Engineers