Some Effects of Irradiation on Nylon and Polyethylene Terephthalate

Abstract

IN a detailed paper by Charlesby¹ on the effects of irradiation on polyethylene, he suggested that the main effect was ‘cross-linking’, that is, the formation of covalent bridges between neighbouring molecular chains, with the consequent loss of hydrogen. Since then, there has been a tendency to refer to the effect on any polymer as ‘cross-linking’ when low irradiation doses show changed solubilities in normal solvents, increased melting points, and no gross chemical breakdown², although other possible causes for these changes have been suggested³. It seems appropriate, therefore, to describe experiments on two of the polymers which have been specifically mentioned by Charlesby and Lawton, 66 nylon and ‘Terylene’.