Photo-oxidation Of Polypropylene Under Load

We have studied the photo-oxidation of isotactic polypropylene films under mechanical load. These films were either slightly or highly oriented, with or without photoprotecting agents. The oxidation reactions were followed by carbonyl index determinations from IR spectra. The results indicate that the oxidation rate can be related to mechanical load, polymer morphology and the intensity of the light source. In the earlier stages of the photo-oxidation, the static load can act as a protector against oxidation, in a similar manner to that observed with highly oriented samples. © 1993.4015358Allen, (1983) Degradation and Stabilization of Polyolefines, p. 213. , Applied Science Publishers, LondonPopov, Krisyuk, Zaikov, (1980) Dokl. Akad. Nauk USSR, 253, p. 1169Popov, Krisyuk, Blinov, Zaikov, (1981) Eur. Polym. J., 17, p. 169Rapoport, Livanova, Grigor'yev, Zaikov, Influence of the electrode potential and of solvents on the process of polymer film formation during the electrochemically initiated polymerization of methacrylatemethyldiethoxymethyl silane (1983) Polymer Science U.S.S.R., 25 A, p. 2188Rapoport, Zaikov, (1984) Eur. Polym. J., 20, p. 409Benachour, Rogers, (1981) Am. Chem. Soc. Symp. Ser., 151, p. 266Livanova, Rapoport, Miller, The degradation and stabilization of cellulose acetates and of some vinyl fluoride polymers. Review (1978) Polymer Science U.S.S.R., 20 A, p. 1893Binder, Stangl, (1975) Chem. Kunsts. Aktuell., 29, p. 223Czerny, Thermo-oxidative and photo-oxidative aging of polypropylene under simultaneous tensile stress (1972) Journal of Applied Polymer Science, 16, p. 2623Baumhardt-Neto, De Paoli, (1990) Quim. Nova, 13, p. 104Baumhardt-Neto, R. & De Paoli, M.-A., Polym. Degrad. & Stab. (in press)Popov, Krisyuk, Zaikov, (1980) Polym. Sci. USSR, 22 A, p. 1501Carlsson, Wiles, The Photooxidative Degradation of Polypropylene. Part I. Photooxidation and Photoinitiation Processes (1976) Journal of Macromolecular Science, Part C: Polymer Reviews, 14 C, p. 6