Photo-induced Structural Changes In Polyolefin-nanoclay Composite

摘要

The morphology of films prepared by melt-blending polyethylene (PE) and polypropylene (PP) with and without nanoclay was investigated after exposure to outdoor solar radiations for 45 days utilising many techniques. The Raman spectra revealed decreased intensity for all the characteristic Raman bands for PP and PE. The Fourier transform infrared spectroscopy showed formation of hydroxyl/hydroperoxy and carbonyl groups in the exposed samples. The weathered films after 45 days of solar exposure became brittle as indicated by loss in physical properties and the stress-strain curves. The clay-containing films showed higher strength loss after solar exposure. The fractured ends of the exposed films showed flat, smooth, and sharp surfaces, indicative of brittle fracture, compared to the unexposed sample.