Multifunctional polyurethanes synthesized from different triarylamine units with electrochromic, photogeneration, memory storage and sensing properties

In this work, a series of multifunctional polyurethane (PU) materials containing three kinds of different triarylamine (TAA) units was prepared. These polymers show good solubility in common organic solvents and excellent thermal stability under a N₂ atmosphere. The PU films show reversible color changes with high contrast ratios and electrochromic stability. Moreover, they have good memory storage performance. The ON/OFF current ratio is about two orders of magnitude. Meanwhile, they can be used as detectors for 2,4,6-trinitrotoluene (TNT) and 2,4,6-trinitrophenol (TNP). The polymer solutions rapidly exhibit fluorescence-quenching phenomena when exposed to trace amounts of TNT and TNP. The PU films also have mechanical properties that make them suitable for use in stretchable devices.