Synthesis of novel poly(aryl ether amide)s containing the phthalazinone moiety

Two novel heterocylic diamine monomers: l,2‐dihydro‐2‐(4‐aminophenyl)‐4‐4‐(4‐aminophenoxy) phenyl]‐(2H)‐phthalazin‐l‐one and 1,2‐Dihydro‐2‐( 4‐aminophenyl )‐4‐[4‐(4‐aminophenoxy‐3, 5‐dimethylphenyl]‐(2H)‐phthalazin‐1‐one were successfully synthesized using readily available heterocyclic bisphenol‐like monomers through two steps in high yield. A series of novel poly(aryl ether amide)s containing the phthalazinone moiety with inherent viscosities of 1.16–1.67 dL/g were prepared by the direct polymerization of the novel diamines and aromatic dicarboxylic acids using triphenyl phosphite and pyridine as condensing agents. The polymers were readily soluble in a variety of solvents such as N,N ‐dimethylformamide (DMF), N,N‐dimethylacetamide (DMAc), dimethylsulfoxide ( DMSO ), N‐methyl‐2‐pyrrolidinone (NMP), and pyridine. The polymers had high glass transition temperatures ( T_g) in the 291–329°C range.