Thomas X. Neenan

Amphiphilic polyphosphazenes as membrane materials: influence of side group on radiation cross-linking

The amphiphilic mixed-substituent polyphosphazenes, [NP(OCH2CF3)x (NHCH3)y)]n and [NP(OC6H5)x (NHCH3)y]n, have been prepared by the sequential replacement of chlorine in [NPCI2]n by trifluorethoxide or phenoxide and methylamine. Thin films of these species were cross-linked by exposure to gamma radiation and the semipermeability of the resultant membranes was monitored. The radiation-induced cross-linking and membrane-forming properties of these polymers were compared with those of the single substituent polymers, [NP(OCH2CF3)2]n, [NP(OC6H5)2]n, and [NP(NHCH3)2]n. The radiation-cross-linking and appeared to involve free radical reactions at the methyl groups of the methylamino substituents. The possible utility of these materials in biomedical research is discussed.

Synthesis of a heparinized poly(organophosphazene)

The synthesis of a new potential anti-thrombogenic polymer is described. Limited halogenation of an aryloxy-substituted polyphosphazene, followed by quaternization with triethylamine yielded a polymer capable of forming polyelectrolyte complexes with sodium heparin. The results of preliminary clotting tests with bovine blood are presented.

Synthesis, oxygen-binding behavior, and Moessbauer spectroscopy of covalently bound polyphosphazene-heme complexes

Effet de la liaison covalente entre un support polyphosphazene hydrosoluble et deux metalloporphyrines sur la fixation doxygene et les proprietes delectrolyse de ces systemes