Effect of photoirradiation on potassium persulfate-surface oxidation of low-density polyethylene film

Surface oxidation of low-density polyethylene (PE) film (thickness = 30 mum) with potassium persulfate (KPS) was investigated at 50 degreesC in water. The surface oxidation was followed by ATR-IR measurement of the oxidized PE film, where the absorbance ratio of the carbonyl group at 1716 cm(-1) to the methylene group at 1460 cm(-1) was used as a measure of the oxidation. The absorbance ratio increased with increasing the reaction time (similar to 12 h) and the concentration of KPS (0.01-0.30 mol/l). The decomposition of KPS was largely accelerated by photoirradiation (lambda > 290 nm), resulting in the promoted surface oxidation of PE film, by which hydroxyl groups were introduced on the oxidized surface. Vinyl monomers such as acrylamide, N-isopropylacrylamide and glycidyl methacrylate could be grafted onto the oxidized surface using eerie salt initiator, which was confirmed by ATR-IR measurement of the grafted films. (C) 2001 Elsevier Science Ltd. Ail rights reserved.