Electrochemically induced derivatization of poly(2,2′-bithiophene) and characterization of functionalized polymers by FT-IR microscopy, SEM microanalysis and EQCM

In this paper, we present a study of an innovative way of preparing and characterizing functionalized conducting polymers. Instead of electropolymerizing the pre-functionalized monomer, with a procedure that must be optimized for many experimental aspects, the functionalization of the pre-electropolymerized film on a polarizable electrode is proposed and discussed here. The alkoxylation of pre-electropolymerized poly(2,2′-bithiophene) films, deposited on platinum or gold electrodes, was carried out by electrooxidative treatment of the polymers under several different experimental conditions, in acetonitrile solutions of 2-bromoethanol or 2-chloroethanol. Electrofunctionalization has been carried out potentiostatically, i.e. by keeping the potential at a fixed value, or by cycling it between oxidising and reducing values. The highest yields have been reached potentiostatically. The proposed mechanism for the functionalization reaction is supported by the results of scanning electron microscopy and reflectance-mode FT-IR microscopy, which have been interpreted by means of chemometric techniques.