Novel polyamides containing asymmetric diamine designed and synthesized towards electrochromic and resistance memory device

Electrochromic (EC) materials have captured intense attentions in the field of smart window, label screen and camouflage recently. The structure of EC active group is crucial to the properties of product. In this study, novel PAs with EC and memory properties were developed by polycondensation of asymmetry triarylamine N, N'-bis(4-aminophenyl)-N-isopropyl-N'-phenylbenzene-1,4-diamine (IPATAA) with five different dicarboxylic monomers. An isopropyl group of the IPATAA molecule is linked to a nitrogen atom to increase electron density and solubility. Furthermore, PAs are apt to be processed into a film by spin-coating or printing. After electro-oxidation, PAs films change from colorless to blue. The coloring time and bleaching time is 2.8–4.1 s and 2.6–4.5 s, respectively. The highest coloring efficiency of PAs film is 366 cm² C⁻¹. Memory devices made using the PAs show non-volatile memory characteristics such as lower switching threshold voltages (<1.08 V) and better switching current ratios (>2 × 10⁴).