SYNTHESIS AND PHYSICAL-PROPERTIES OF POLY(ARYL ETHER PHTHALAZINE)S

The synthesis of a new class of polymers, the poly(aryl ether phthalazine)s, is described via an intramolecular ring-closure reaction of poly(aryl ether ketone)s containing the o-dibenzoylbenzene moiety with hydrazine monohydrate. The synthesis of copolymers of poly(aryl ether ketone)s and poly(aryl ether phthalazine)s is demonstrated, and the copolymer ratios were determined by H-1 NMR studies. Various fluoro-substituted phthalazine monomers were prepared and polymerized with bisphenols in N-methyl-2-pyrrolidinone (NMP) in the presence of excess base (K2CO3). High molecular weight polymers were obtained, with glass transition temperatures in the 235-340-degrees-C range. Thermal stabilities for the resulting materials by TGA showed polymer decomposition temperatures (5% weight loss) in air and in nitrogen ranging from 460 to 535-degrees-C. The polymerization of 3,6-bis(4-fluorophenyl)pyridazine with 4,4'-(1-methylethylidene)-bisphenol (BPA) also afforded a new class of polymers, the poly(aryl ether pyridazine)s.