SYNTHESIS AND CHARACTERIZATION OF NOVEL CYCLOTRIPHOSPHAZENE-CONTAINING POLY(ETHER IMIDE)S

Novel cyclotriphosphazene-containing poly(ether imide)s have been developed by nucleophilic displacement of active nitro groups of tris[4-(3'-nitrophthalimido)phenoxy]tris(phenoxy)-cyclotriphosphazene (I) or tris[4-(4'-nitrophthalimido)phenoxy]tris(phenoxy)cyclotriphosphazene (II) and a bisnitrophthalimido derivative by the dianion of bisphenol A. The synthesized polymers were characterized by Fourier-transform infra-red and H-1, C-13 and P-31 nuclear magnetic resonance spectroscopy, differential scanning calorimetry (d.s.c.) and thermogravimetric analysis (t.g.a.). The d.s.c. of the polymers demonstrated glass transition temperatures in the range of 179-184-degrees-C. The thermal stabilities of the polymers were evaluated in nitrogen and in air by dynamic t.g.a. The synthesized polymers were thermally stable. The dynamic t.g.a. showed thermal decomposition starting at 410-415-degrees-C and char yield of 59-42% in nitrogen at 800-degrees-C and 30-32% in air at 700-degrees-C. Gel permeation chromatography showed a weight-average molecular weight of the polymer of 6.5 x 10(3). The polymer prepared from cyclotriphosphazene monomer I showed thermoplastic melt processing at 250-degrees-C to tough film and moulding.