Hr. Allcock et al., Synthesis of trifluoromethyl- and methylphosphazene polymers: Differences between polymerization and initiator/terminator properties, MACROMOLEC, 32(24), 1999, pp. 7999-8004
A new polyphosphazene, [N=PPh(CF3)](n), has been prepared via the PCl5-indu
ced cationic polymerization of Me3SiN=P(CF3)(Ph)Br. In addition, the cation
ic route has been used to produce [N=PPh(Me)](n) with controlled molecular
weights and narrow polydispersities. By contrast, the new monomer Me3SiN=P(
t-Bu)(Ph)F failed to polymerize under any conditions but was used as an ini
tiator and terminator to prepare both mono- and ditelechelic polymers. This
monomer was also used to prepare [F(Ph)(t-Bu)P=N(PCl2=N)P(t-Bu)(Ph)F](+),
which was used as a substrate for reactions with alkoxy and aryloxy groups
to yield the hydrolytically stable materials, [R(Ph)(t-Bu)P=N(PR2=N)P(t-Bu)
(Ph)R-2].