Study of Degradation Behavior of ASA Coated PVC Roofing Sheets

Polyvinyl Chloride (PVC) based roofing sheets are widely used in industrial and domestic applications today. It is recognized that ultraviolet rays (UV) in sunlight (wavelengths between 280 nm and 400 nm) cause photodegradation of some organic materials including polymers. Therefore, studying the change in properties of PVC/Acrylonitrile Styrene Acrylate (ASA) roofing sheets due to weathering is essential for their successful application. From this study, it was attempted to study how photodegradation affects some properties like hardness and impact strength of the roofing sheet. It was evident from the UV exposure test data that prolonged exposure to UV radiation deteriorates the hardness and impact strength properties of the sheet. But no change in appearance was observed in both UV exposure test and accelerated weathering test.