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The synthesis of polyphosphazene-co-poly(ethylene oxide) block copolymers with well-defined molecular weights has been accomplished via end-functionalized polymer intermediates. Mono-and diamine-terminated poly(ethylene oxides) (PEO ) (CH 2CH2O)n-CH2CH2-) were used to produce polymerbased phosphoranimines, CH3O-(CH2CH2O)n-CH2CH2-NH(CF3CH2O)2PdNSiMe3 and Me3SiNdP(OCH2-CF3)NH-(CH2CH2O)n-CH2CH2-NH(CF3CH2O)2PdNSiMe3. These were then converted to macroinitiators via reaction with PCl5 to produce CH3O-PEO-NH[(CF3CH2O)2PdNPCl3] + [PCl6]and [Cl3PNdP(OCH2-CF3)NH-PEO-NH[(CF3CH2O)2PdNPCl3] 2+[PCl6]2 -, respectively. These macroinitiators were used to polymerize Cl3PdNSiMe3 in a living manner to produce diblock copolymers of polyphosphazenes with poly(ethylene oxide) or triblock copolymers with poly(ethylene oxide) blocks flanked by polyphosphazene components. In addition, the monophosphoranimine-terminated PEO was employed as a terminator in the living, cationic polymerization of Cl3PdNSiMe3 to produce triblock copolymers with a polyphosphazene block flanked by two poly(ethylene oxide) blocks. Polymers for use as solid-ionic conduction media or hydrogels were produced by nucleophilic replacement of the chlorine atoms along the polyphosphazene segments by methoxyethoxyethoxy units. The ionic conductivities of these materials, after complexation with varying ratios of lithium triflate, ranged from 7.6 × 10 -6 to 1.0 × 10 -4 S cm -1 for a temperature range of 20-80 °C.

Polystyrene and poly(methyl methacrylate) copolymers with cyclophosphazene side groups have been prepared by the reactions of azidocyclophosphazenes with diphenylstyrylphosphine residues in the copolymer structures. The cyclophosphazene pendent groups were present in from 1 to 100% of the monomer residues in polystyrene and from 2 to 20% of the repeating units in poly(methyl methacrylate). In both systems, the cyclophosphazene side units lowered the T g roughly in proportion to their concentration in the macromolecules. The presence of ∼10% of cyclophosphazene-bearing monomer residues markedly reduces the combustibility of both polystyrene and poly(methyl methacrylate). The mechanism of fire retardance is discussed.

The synthesis of phosphazene cyclic trimers with azido side groups and aryloxy, alkoxy, or dialkylamino cosubstituent groups was accomplished. The compounds have the basic structure N(3)P(3)(R)(x)()(N(3))(6)(-)(x)(), where R represents phenoxy, trifluoroethoxy, dimethylamino, or diethylamino groups and x = 3-5. Experiments were also conducted to determine the ability of these materials to undergo a reaction unique to azido compounds known as nitrene insertion. The aryloxy derivative, N(3)P(3)(OC(6)H(5))(5)(N(3)), yielded a nitrene insertion product when heated with 1-phenylnonane at 280 degrees C. The alkoxy derivative, N(3)P(3)(OCH(2)CF(3))(5)(N(3)), produced a nitrene insertion product when ultraviolet irradiated in an aliphatic solvent. The dialkylamino derivative, N(3)P(3)(N(CH(3))(2))(4)(N(3))(2), did not undergo nitrene insertion. The aryloxy and alkoxy azido trimers reacted with various phosphorus(III) compounds to form phosphinimines via the Staudinger reaction. Finally, sodium phenoxide displaced azides from both the alkoxy- and aryloxyphosphazene trimers while n-butylamine displaced only the azide on the alkoxy trimer.

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