New polyphosphazenes with unsaturated side groups: Use as reaction intermediates, cross-linkable polymers, and components of interpenetrating polymer networks

A number of new poly(organophosphazenes) have been synthesized which bear 2-butenoxy or (4-(allyloxy)phenyl)phenoxy side groups. Cosubstituent groups included trifluoroethoxy, phenoxy, or (benzyloxy)phenoxy groups. Species with (4-(allyloxy)phenyl)phenoxy units underwent Si-H coupling with linear silanes or siloxanes to extend the side groups and form hybrid phosphazene/organosilicon polymers. A number of these polymers are rubbery elastomere which are readily cross-linked by heat or light. Seven of the mixed-substituent, cross-linked polymers were incorporated into interpenetrating polymer networks (IPN;s) with polystyrene, poly(methyl methacrylate), polyacrylonitrile, poly(acrylic acid), and poly(dimethylsiloxane). The phase compatibility characteristics of the IPN's were assessed by DSC, TEM, FT-IR spectroscopy, and ¹H and ³¹P NMR spectroscopy data.