Macromolecules, Vol.35, No.23, 8728-8737, 2002
Poly(arylene ether)s containing 1,2,4-triazole and phthalimide or naphthalimide moieties joined by a N-N linkage
The synthesis and characterization of new monomers and polymers containing the 1,2,4-triazole group are described. A model reaction of 4-N-amino-3,5-diphenyltriazole with phthalic and naphthalic anhydride demonstrated the preparation of the 1,2,4-triazole-imide compounds containing a N-N linkage. From 4-amino-3,5-bis(4-hydroxyphenyl)triazole four new bisphenols with pendent phthalimide or naphthalimide moieties linked through a N-N linkage were prepared in a one-step reaction in high yield. Poly(aryl ether)s were synthesized from these bisphenols, or their carbamate derivatives, by reaction with various activated arylene difluorides. The reactions were carried out in DMSO in the presence of potassium carbonate to yield high molecular weight, amorphous, and thermally stable polymers with pendent imide moieties joined by a N-N linkage. A new bisphenol with A pendent 3,5-diphenyl-1,2,4-triazole was prepared by an imidization reaction of an anhydride bisphenol with 4-amino-3,5-diphenyltriazole. Polymerization with activated difluoro compounds gave poly(aryl ether)s with a pendent 1,2,4-triazole moiety. These polymers had high T-g's, from 222 to 283 degreesC. Copolymers containing the 1,2,4-triazole in the polymer backbone as well as pendent were also prepared. Using decafluorobiphenyl as coreactant, extremely high molecular weight polymers were obtained at lower polymerization temperature, 90 - 100 degreesC, in a shorter reaction time. The polymers formed clear, transparent, flexible, and tough films from DMF solution. Many of the polymers showed strong blue to greenish-yellow fluorescence from 428 to 510 nm in solution and in the solid state under UV, depending upon the monomer composition of the polymer.