Amorphous phase polyphosphazenes

A wide- and small angle X-ray diffraction study of crosslinked (134) has shown the presence of two phases, viz. an amorphous phase and a two-dimensional ordered phase. Changes of the ordered structure depend on the ion-exchange capacity of the polymer and extent of water swelling. Pervaporation membranes have been prepared by thermally crosslinking of polyphosphazenes bearing p-methoxyphenoxy, methoxyethoxyethoxy and o-allylphenoxy groups in the presence of a radical initiator. ... 

Polyphosphazenes are partially crystalline polymers whose degree of crystallinity is a function of the conditions of preparation of the samples. The glass transition temperature of the amorphous phase is determined by the type of substituents at the phosphorus atom. The Tg for a series of polyphosphazenes in which the existence of mesophases has been reliably established [42] are reported in Table 4.4. The two-stage transition of the crystalline phase through the mesomorphic phase into an isotropic melt was established in [41-42]. The values of the temperatures of the phase transitions for a sCTies of polyphosphazenes are reported in Table 4.4. In polyaryloxyphosphazenes, T,- are close to. 

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