Study of the polymers obtained by electroreduction of methacrylonitrile

In this work, we studied the electrochemical formation of polymethacrylonit rile by cathodic polarization in an anhydrous organic medium, at two differ ent working potentials either side of the potential of the high concentrati on reduction pre-peak. In both cases, the polymer formed in solution and th e so-called grafted polymer were obtained. A detailed analysis has been per formed by infrared reflection absorption spectroscopy for the polymer chemi sorbed on the cathode surface, and by size exclusion chromatography, infrar ed and C-13 nuclear magnetic resonance for the polymer obtained in solution . These analyses reveal essentially no difference, in terms of products of reaction, between the synthesis carried out at the two working potentials, and suggest that the grafting reaction is probably disconnected from the oc currence of the pre-peak. On the contrary, it is proposed that this peculia r peak is due to the dynamic formation of the polymer in solution, and that this hides all effects possibly stemming from surface chemical reactions. (C) 2001 Elsevier Science B.V. All rights reserved.