| Abstract: | The effect of ferric chloride (FeCl3) on photodegradation of isotactic polypropylene (PP) was investigated using mainly ESR spectrometry. PP powder, its oxidized samples, and FeCl3-adsorbing PP samples were irradiated under a nitrogen atmosphere at 77°K with ultraviolet light from a high-pressure mercury lamp and a superhigh-pressure mercury lamp modified by various filters. Methyl, polymerci alkyl, and peroxy radicals were observed in the ESR spectra of the irradiated samples, and it was found that FeCl3 depresses the formation of alkyl radicals and accelerates the formation of peroxy radicals catalyzing the reaction. From infrared study of UV-irradiated film samples, it was also inferred that FeCl3 accelerates the photodegradation the hydroperoxide and carbonyl groups. |
