Polymer radiolysis

In the case of radio-oxidation, a second important source of radicals is the polymer radiolysis, i.e. the breakdown of lateral bonds in the polymer chain. PE radiolysis leads to the formation of very reactive radicals which recombine rapidly by hydrogen abstraction. Thus, the balance reaction can be written as follows ... 

Besides the use in F2 and F2 immersion lithography, fluoropolymers are used in various fields. Fluoropolymer is one of the candidate for a polymer for MEMS, and fabrication of fluoropolymers by ultra-short pulsed lasers (9), and synchrotron radiations (10) has been studied. Polymer outgassing as well as the micro- and nano-fabrication depends on the polymer radiolysis. It is important for the micro- and nano-fabrication to investigate outgassing characteristics which is obvious outcome in the polymer radiolysis. 

The preceding discussion elucidated a few of the problems associated with polymer radiolysis in association with transuranic waste materials. The actual systems are very complicated and involve mixtures of materials and different phases. Considerable time and effort must be committed to fundamental research on solving these problems of major concern to society. A few of the many unresolved radiation chemistry issues involved in the management of transuranic waste materials are ... 

We shall then summarize the data on reactive intermediates and the changes in the chemical and physical properties induced by irradiation, more detailed results on individual polymers being referred to the following sections. Finally, some important industrial applications will be cited. General reviews of the field of polymer radiolysis are given in Refs. 1—3. 

The complete reaction scheme for polymer radiolysis in solution is [443]... 

Elementary reactions (65), (66), (69), (70) and (71) are specific to solutions. Steps (65) and (66), respectively, induce protection or sensitization of polymer radiolysis. Their existence is, however, often difficult to demonstrate and even more difficult to predict. Reactions (69) and (71) are responsible for inhibition of the radiolysis while step (70) leads to an increase in the free radical yield. 

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