Synthesis and Properties of Fully Triphenylamine-based Polyamides Bearing 3,5-bis(Trifluoromethyl) and/or 3,5-dimethyl Substituents on the Pendent Phenyl Units.

Four new fully triphenylamine-based polyamides coded as polyamide (CF3,CF3), polyamide (CF3,CH3), polyamide (CH3,CF3), and polyamide (CH3,CH3) were synthesized by the phosphorylation polyamidation reaction from various combinations of 3,5-bis(trifluoromethyl)-4′,4″-dicarboxytriphenylamine, 3,5-dimethyl-4′,4″-dicarboxytriphenylamine, 3,5-bis(trifluoromethyl)-4′,4″-diaminotriphenylamine, and 3,5-dimethyl-4′,4″-diaminotriphenylamine. All the polyamides were amorphous and readily soluble in many common organic solvents and could be solution-cast into transparent, flexible, and strong films with good mechanical properties. They had useful levels of thermal stability associated with high glass-transition temperatures of 268–287°C and 10 wt%-loss temperatures in excess of 500°C. Cyclic voltammograms of the film of polyamide (CH3,CH3) on the indium-tin oxide-coated glass substrates exhibited two oxidation redox couples withE1/2around 0.82 and 1.29 V vs. Ag/AgCl in tetrabutylammonium perchlorate/acetonitrile solution, accompanied by a color change from pale yellow neutral state to dark green oxidized state. The CF3-substituted polyamides displayed a higher oxidation potential and less electrochemical stability as compared to the CH3-substituted analogues. [ABSTRACT FROM PUBLISHER]