Structure and Conductivity in Substituted Polypyrroles. Part 1. Synthesis and Electropolymerization of N-Trimethylsilylethoxymethyl-3-methyl-4-pyrrole Carboxylate Ethyl Ester

The electrochemical polymerization of N-trimethylsilylethoxymethyl-3-methyl-4-pyrrole carboxylate ethyl ester (MPCE-SEM) in the presence of pyrrole, to give free-standing copolymer films is described. These films have been characterized by surface conductivity measurements, reflectance FTIR spectroscopy, X-ray photoelectron spectroscopy and scanning electron microscopy. Increasing the relative concentration of MPCE-SEM in the polymerization solution resulted in an increase in the proportion of these units in the copolymer film. Increasing the proportion of MPCE-SEM units in the copolymer resulted in a decrease in surface conductivity. This is consistent with expectation because N-substituted polypyrroles tend to have lower conductivity values than unsubstituted polypyrrole. Significantly, it has also been shown that the N-protecting group of the MPCE-SEM unit can be removed after polymerization under mild conditions in a solid phase deprotection procedure.