POLY(HALOPHOSPHAZINES) AS SUBSTRATES FOR POLYMER SYNTHESIS.

This paper is concerned with the chemistry of linear polyphosphazenes whose synthesis is different from that of all other synthetic macromolecules: (a) the reaction sequence utilizes a highly reactive polymer (II) as an intermediate for the preparation of stable derivatives; and (b) because of the unusual model of synthesis, large numbers of different polymers with diverse and unusual properties can be prepared by the use of the wide variety of alcohols, phenols, primary or secondary amines, and organometallic reagents either singly or to form mixed substituent polymers. Even with the presently known reactions, the number of accessible organophosphazene polymers probably exceeds that of all the known organic polymers prepared by conventional vinyl, condensation, and ring opening techniques. The purpose of this paper is to examine some of the finer points of the substitution reactions of II and to illustrate how organic side groups attached to a polyphosphazene chain may themselves undergo condensation reactions in a way that further increases the scope of this field.