Photochemical investigations into cellulosic materials I. Free radical generation in cellulose by photosensitized excitation

UV irradiation of cellulose, both in photosensitized and unphotosensitized experiments results in chain scission and radical generation on the glucosidic cycle, as observed by ESR spectroscopy. It was shown that sensitizers of the benzoin and benzophenone family induce radicals very efficiently on cellulose. The results obtained with several benzoin derivatives and benzophenone are discussed in connection with the ESR spectra, in terms of the primary processes involved during the photolysis of these compounds in cellulose. Features relevant to photografting are derived from these experiments.