SYNTHESIS, CHARACTERIZATION, AND MODIFICATION OF 2-ALLYLPHENOXYORGANOCYCLOTRIPHOSPHAZENE COPOLYMERS

The monomer 2-allylphenoxyorganocyclotriphosphazene I with phenoxy (or 2,2,2-trifluoroethoxy) side group was synthesized on reacting hexachl orocyclotriphosphazene with phenol (or 2,2,2-trifluoroethanol) and 2-a llylphenol with phase-transfer catalysis in a dichloromethane/alkaline solution. The synthesis had a large yield (>80%) and narrow product d istribution and proceeded under mild condition. The radical copolymeri zation of I with II (styrene, methyl methacrylate, and vinylbenzyl chl oride) using azobis(isobutyrylnitrile) (AIBN) as an initiator was inve stigated. Reactivity ratios and Alfrey-Price parameters for copolymers were obtained. Organophosphazene monomer I was less reactive than II. The thermal stability of the copolymer with phenoxy side group was gr eater than that with 2,2,2-trifluoroethoxy side group. The incorporati on of organophosphazene units into an organic polymer backbone decreas ed the glass transition temperature and increased the thermal stabilit y of the copolymers. Tensile measurement showed that Young's modulus t ended to decrease and the polymer became softer and ductile when the i ncorporated amount of I increases. (C) 1996 John Wiley & Sons, Inc.