Thermoplastic and thermosetting poly(arylene ether aryl phosphine oxide)s via melt polymerization: synthesis and characterization

The melt polymerization of poly(arylene ether phosphine oxide)s via the silylation route was investigated as a method for obtaining easily melt processable, tough, transparent, high T_g fire resistant materials which have potential to be used in aerospace applications. Polymers synthesized in solution via nucleophilic processes produce large amounts of salt by-product, which requires additional steps for removal. Melt polymerizations provide a directly processable polymer melt, with the possible further formation of film, shetet or polymer optical fibers. Poly(arylene ether phosphine oxide), (Bis A PEPO) based on Bisphenol A or 'AF' and bis(4,4′-fluorophenyl) phenyl phosphine oxide has been studied extensively. The molecular weight of the polymer was controlled by using Carother's Equation. Thermal behavior (Tg, TGA, etc.) of the melt synthesized polymers compared favorably to the solution standard. Thermally reactive phenylethynyl endgroups have also been incorporated into reactive oligomers. Compression molded thermoplastic specimen are optically clear, ductile and show excellent lap shear adhesion to surface treated titanium 6/4 (e.g. 35 MPa).