Synthesis and characterization of a fluorinated phthalazinone monomer 4-(2-fluoro-4-hydroxyphenyl)-phthalazin-1(2H)-one and its polymers from polycondensation reactions

As a category of high performance polymers having good solubility and distinguished thermal properties, poly(phthalazinone ether)s received much attention for their applications in engineering plastics and membrane materials. 2-(2-Fluoro-4-hydroxybenzoyl)-benzoic acid (FHBBA) synthesized from 3-fluorophenol and phthalic anhydride reacted with hydrazine hydrate to form 4-(2-fluoro-4-hydroxyphenyl)-phthlazin-1(2H)-one (FDHPZ). Four polymers were prepared from polycondensation reactions of FDHPZ with 4,4′-difluorobenzophenone, bis(4-chlorophenyl) sulfone, 1,4-bis(4-fluorobenzoyl)-benzene and perfluorobiphenyl, respectively. All polymers show good solubility in common aprotic solvents and have excellent thermal properties investigated by DSC and TGA. FTIR and NMR spectra of FDHPZ, FHBBA, and polymers from FDHPZ were studied. Refractive indices (nTE) of films on silicon substrates were measured with a Prism Coupler. These polymers have potentials as materials for optical waveguides.