Radiation-induced modifications of some poly(aryloxyphosphazenes)

Four polyphosphazenes of general formula [(R-Ph-O)2PN]sub(n), with R denoting H, Me, t-Bu, and cumyl, were exposed to ionizing radiations in a variety of conditions, i.e., in nitrogen and oxygen atmospheres and under vacuum, following the network formation as a function of dose by u.v. determination of the sol fraction; The behaviour observed in the various conditions was discussed and the susceptibility of each polymer to undergo crosslinking and chain scission was approximately assessed. In order to account for the widely different G(X) and G(S) values found, some investigations were carried out by ESR analysis on the different nature and amount of the radical intermediates produced in the irradiation of the four polyphosphazenes. (author)