SYNTHESIS AND THERMAL-REACTION OF ACETYLENIC GROUP SUBSTITUTED POLY(ORGANOPHOSPHAZENE)S AND CYCLOTRIPHOSPHAZENE

Poly[bis[4-[(trimethylsilyl)ethynyl]anilino]phosphazene] was prepared by reaction of poly-(dichlorophosphazene) with 4-[(trimethylsilyl)ethynyl]aniline. Cosubstituent poly(organophosphazene)s were synthesized by sequential reaction of poly(dichlorophosphazene) with 4-[(trimethylsilyl)ethynyl]aniline and sodium trifluoroethoxide. Trimiethylsilyl groups were removed by treating the polymers with aqueous KOH in methanol to give acetylene-substituted polyphosphazenes. These polymers were soluble in common organic solvents including acetone, methanol, NN-dimethylformamide, and dimethyl sulfoxide. Thermal reactions of the polymers were studied by means of differential scanning calorimeter (DSC) and IR. Cross-linked polymer films were obtained by molding the polymers at 180-degrees-C under pressure. Hexakis-(4-ethynylanilino)cyclotriphosphazene was also prepared from hexachlorocyclotriphosphazene, and its thermal reaction was studied by DSC and IR. DSC measurement for the compound demonstrated a cure onset temperature at 180-degrees-C and a cure maximum temperature of 236-degrees-C.