SYNTHESIS OF POLY(DICHLOROPHOSPHAZENES) FROM CL3P=NP(O)CL2 .1. KINETICS AND REACTION-MECHANISM

Type Cl3P = N(PCl2 = N)n-1P(O)Cl2 poly(dichlorophosphazenes) have been synthesized by solution polycondensation of P-trichloro-N-(dichlorophosphoryl)monophosphazene, Cl3P = NP(O)Cl2. Monitoring the progress of the reaction using P-31 NMR spectroscopy allowed us to determine an order of magnitude of the reactivity ratio for the species n = 1-4 and to propose a mechanism. The results obtained enabled us to prepare a range of polymers with an intrinsic viscosity varying in the solvent THF at 30-degrees-C from 10 to 72 mL/g and to establish the Mark-Houwink relationship in the same solvent.