Organophosphazenes. 19. Copolymerization of 2-(2-Ethoxyvinyl) pentafluoro cyclotriphosphazene with Styrene and Methyl Methacrylate

摘要

The novel cyclophosphazene, 2-(2-ethoxyvinyl)pantafluorocyclotri phosphazene (N3P3F5C(OC2H5)=CH2) undergoes radical copolymerization with styrene and methyl methacrylate. The styrene system was examined in detail with flame retardant copolymers having up to 43.7% phosphazene content being obtained. Reactivity ratios for the styrene-ethoxyvinyl phosphazene copolymerization have been calculated by several methods. An examination of the Alfrey-Price parameters for the phosphazene indicates that the major perturbation of the olefinic center is through the sigma electron withdrawing effect of the phosphazene. The copolymer molecular weights decrease with increasing phosphazene content. The thermal decomposition of the copolymers is a two step process with the phosphazene being involved in the first step.