POLYPHOSPHAZENE RANDOM AND BLOCK-COPOLYMERS WITH ALKOXYALKOXY AND TRIFLUOROETHOXY SIDE-GROUPS

The synthesis of N-silyl-phosphoranimines bearing mixed alkoxyalkoxy and trifluoroethoxy substituents is reported. The polymerization kinetics and the proposed anionic mechanism are also discussed. These monomers are utilized for the preparation of polyphosphazene random copolymers by the simultaneous polymerization of two phosphoranimines. Block copolymers have also been synthesized by addition of a second phosphoranimine after conversion of the first. Evidence for copolymer formation includes H-1 and P-31 NMR, SEC, solubility and DSC data. The differences between analogous random and block copolymers are discussed.