General Effects of Electron Beam on Polymers

General effects of electron beams on polymers have been recently discussed by Bhowmick [3]. Since chemical bonds only require a few ev for destruction, it might be expected that the incident radiation of an electron beam of typically several million ev would cause bond destruction at random. In fact, this is not so. The reactions involved are remarkably selective [4]. The reactions are primary and secondary in nature. Primary reactions are two folds Ionization, the production of an ion and excitation, the formation of fast electrons of excited chemical species [5]. 

In the secondary reactions, the excited ions dissociate into a radical ion and a radical. 

With further reactions, excited molecules are formed. These may dissociate into secondary ions, molecular products and free radicals. The polymers may then undergo chain scission, crosslinldng and recombination of broken chains. 

Poly(chlorotrifluoro ethylene) Poly(vinyl acetate) 

Poly(methyl methacrylate) Poly(vinyl alcohol) 

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