Large stabilizing effect of titanium dioxide on photodegradation of PVC/α-methylstyrene-acrylonitrile copolymer/impact modifier-matrix composites

A large stabilizing effect was obtained via adding titanium dioxide (TiO₂) into poly (vinyl chloride)/α-methylstyrene-acrylonitrile copolymer/impact modifier blends. A comparison between photodegradation of blends (without TiO₂) and composites (with TiO₂) was conducted. Results of color difference, surface morphology, and thermogravimetric analysis tests indicated the higher UV resistance of composites than blends. Composites exhibited a almost unchangeable tensile strength and a certain retention rate of elongation at break; while drastic loss in these two properties were observed for blends. Fourier transform infrared and rheological tests also revealed the stabilizing effect exerted by TiO₂, and it was found that different systems exhibited different stabilizing mechanisms. POLYM. COMPOS., 35:2365-2375, 2014.