Synthesis of aromatic poly(pyridinium salt)s and their electrochromic properties

Synthesis of a series of new conjugated electrochromic polymeric pyridinium salts containing main-chain triphenylamine and their electrochromic properties were demonstrated. All polymers exhibit intense UV absorptions at 336–338 nm in DMF and 340–343 nm in thin film form and fluorescence centered at 410–438 nm in DMF and 460–461 nm in thin film form. The electrochromic properties of the films were investigated by electrochemical and spectroelectrochemical methods. Reversible redox signals with stable electrochromic characteristics were obtained via cyclic voltammetry. The electrochromic properties of the polymers remain highly stable after 50 cycles between 0 and 1.2 V.

► The polymer films have high transmissive color in the neutral state (0 V).
► All of the polymers exhibit intense UV absorption and fluorescence both in DMF solutions and in film form.
► The polymer films exhibit multi electrochromic properties.