Electroinitiated polymerization of 2-ethylhexylacrylate on carbon fibers

Abstract

The electroinitiated polymerization of 2-ethylhexylacrylate in dimethylformamide in the presence of tetrabutylammoniumiodide was investigated at 288–314 K, with graphitized monofibers being used as a cathode. Electron microscopy showed that the surface of a carbon fiber is characterized by considerable microheterogeneity. The fiber interaction with the propagating polymer chain was supposed to be different due to the energetic microheterogeneity of the fiber surface. This has been proved by micrographs of carbon fiber samples after electrolysis. The local excrescences of poly (2-ethylhexylacrylate) could not be separated after prolonged acetone extraction of the samples. They were conventionally referred to as a grafted polymer. It is inferred that the energetic surface microheterogeneities have a considerable effect on the grafting process regardless of the nature of the reactive centers. The use of carbon monofibers as a cathode does not substantially affect the mechanism of the 2-ethylhexylacrylate electroinitiated bulk polymerization. It is shown that the solution polymerization of 2-ethylhexylacrylate in dimethylformamide occurs according to an anionic mechanism and leads to oligomer formation. The experimental rate constants of the electroinitiated polymerization of 2-ethylhexyl-acrylate, depending on current density and temperature, as well as the total activation energy were determined.