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Studies in the field of polyethylene—IV.: Influence of γ-radiation on the structure and molecular weight of the AS polyethylene

✍ Scribed by D.A. Isǎcescu; I.V. Ionescu; V. Kenyereş-Ursu; I. Petrus; Gh. Furnicǎ; A. Caragheorgheopol


Publisher
Elsevier Science
Year
1970
Tongue
English
Weight
764 KB
Volume
6
Category
Article
ISSN
0014-3057

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✦ Synopsis


A study was made of effects of 6°Co ~,-radiation on the average mol. wt. and the structure of AS polyethelene obtained with amyl-sodium catalyst according to the process of C. D. Nenizescu and co-workers. Examination was made of the viscosimetric characteristics, and the i.r. and electron spin resonance (ESR) absorption spectra for samples irradiated at room temperature and in the presence of air. The spectra were recorded immediately after irradiation and after various lengths of storage at different temperatures.

The ionizing radiation causes an oxidative degradation of AS polyethylene, shown by the decrease of the average mol. wt., and the appearance of characteristic i.r. absorption bands for oxygencontaining groups. The ESR spectra indicate the existence of allyl, alkyl and polyenyl radicals. During storage of the irradiated AS polyethylene especially at high temperature (80°), a slight increase of the oxidative degradation process can be observed.


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