Novel near-infrared and multi-colored electrochromic polybenzoxazines with electroactive triarylamine moieties

Two triarylamine-containing flexible polybenzoxazine films with T-g up to 312 degrees C were prepared by the thermally induced curing reaction of the corresponding polybenzoxazine precursors, which were synthesized by the reaction of paraformaldehyde with bisphenol A and 4,4'-diamino-4''-methoxytriphenylamine (1) or N,N'-bis(4-aminophenyl)-N,N'-di(4-methoxyphenyl)-1,4-phenylenediamine (2). By introduction of triarylamine units into the polybenzoxazine precursors, the resulting solution-processable polybenzoxazine precursor films not only exhibited interesting multi-colored electrochromic behavior with a high contrast ratio both in the visible range and near infrared region (NIR) but also could effectively increase the oxidation stages when compared with their corresponding polyamides.