| Abstract
| - Reaction of the halogenated poly(thionylphosphazene)[NSOCl(NPCl2)2]n(2a), whichpossesses a novel S(VI)−N−P backbone, with 2, 3, and 4 equiv ofNa[OCH2CF3], followed byexcessnBuNH2, afforded mixed-substituentpoly[alkoxy(amino)thionylphosphazenes][NSO(NHnBu)(NPR2)2]n(6)(a, R = 51% OCH2CF3, 49%NHnBu; b, R = 76%OCH2CF3, 24% NHnBu;c, R = 95% OCH2CF3, 5%NHnBu)in which the polymers were regioselectively substituted withtrifluoroethoxy substituents only atphosphorus and not at sulfur. The resulting moisture stablepolymers were structurally characterizedby 31P, 1H, 13C, and19F NMR spectroscopy. Molecular weights were in therange Mw = 3.3 × 104 to1.4× 105 and Mn = 1.9 ×104 to 8.2 × 104 according to GPC analysis inTHF versus polystyrene standards.The thermal transition behavior was investigated by DSC, glasstransition temperatures (Tg's)rangedfrom −30 to −14 °C, and no melt transitions were detected.Analysis of these new polymers by TGAshowed that they were stable to weight loss up to ca. 250 °C undernitrogen at a heating rate of 10°C/min.
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