Novel blue and red electrochromic poly(azomethine ether)s based on electroactive triphenylamine moieties

Two series of red and blue electrochromic aromatic poly(azomethine ether)s (PAMEs) containing electroactive triphenylamine (TPA) moieties in the backbone were prepared from the high-temperature polycondensation reactions of newly azomethine–triphenylamine (AM–TPA)-based biphenol monomers, 4,4′-di(4-hydroxybenzylideneamino)triphenylamine (3) and 4,4′-di(4-hydroxybenzylideneamino)-4″-methoxytriphenylamine (4), with difluoro compounds, respectively. The obtained polymers were readily soluble in many organic solvents and showed useful levels of thermal stability associated with high softening temperatures (215–240 °C) and high char yields (higher than 64% at 800 °C in nitrogen). In addition, the polymer films showed reversible electrochemical oxidation with high contrast ratio and unique anodic blue/red electrochromic behaviors.