Synthesis, spectroscopic and electrochemical characterization of polyurethanes containing triphenylamine derivative

A series of novel conducting polyurethanes (PUs) with methoxyl triphenylamine (methoxyl-TPA) were synthesized from a new isocyanate with various dihydroxy monomers. The new isocyanate was prepared with p-anisidine and 4-fluoronitrobenzene. The structures of the designed polymers had been determined by FT-IR and ¹H NMR. These polymers are amorphous and readily soluble in many polar organic solvents, such as N,N-dimethylformamide, dimethylacetamide and dimethyl sulfoxide. Similarly, the optical band gaps of PU-1, PU-2 and PU-3 are found to be 2.41, 2.51 and 2.44 eV, respectively. In addition, the polymers display excellent thermal stability, reversible electrochemical oxidation, high optical contrast ratio and electrochromic behavior from brown to cyan in the range of 0–1.5 V. High coloration efficiency of PU-2 arrives to 94.17 cm² C⁻¹.