Oxazoline-containing phosphazene derivatives Part II Polymer preparation and modification through the reactivity of oxazoline moieties on cyclophosphazenes

In this paper we report the synthesis, the characterization and the practical utilization of two cyclophosphazenes (CPs) substituted with two (C-2-OXA) and six (C-6-OXA) 2-(4-hydroxyphenyl)-2-oxazoline groups, respectively. The first chemical observation on these substrates is that the reactivity of the oxazoline groups is preserved even when these products are attached to the phosphorus atoms of a cyclophosphazene ring. By reaction of C-2-OXA with organic molecules, e.g. adipic acid, and macromolecules, e.g. poly(ethylene terephthalate) (PET), the oxazoline substituents open their heterocycles to form cyclolinear polymers or to act as chain extenders. Similarly, the ring-opening polymerization reaction of C-6-OXA in the presence of cationic initiators allows the production of a new class of cyclomatrix polymers. The characterization of the new materials is reported.