Abstract
In order to obtain information concerning the adsorption of polyelectrolytes, the differential capacity (C) of mercury-polyelectrolyte solution interfaces was measured at various applied potentials (E) by using Grahame's AC bridge method with the dropping mercury electrode. The polyelectrolytes used were methacryloyloxy-ethyltrimethylammonium methylchloride homopolymer (A) and copolymers of A and acrylamide (B, C).
The C-E curves obtained showed one dynamic peak at cathodic polarization and the capacity suppression over anodic polarization range. The height of dynamic peak (Cp) and the minimum capacity over the zero polarization range (Cmin) depended on polyelectrolyte concentrations. This result could be explained by the increase in the surface coverage with polyelectrolyte molecules and the rearrangement thereof resulting from increasing polyelectrolyte concentrations. It was also found that the values of Cmin observed at sufficiently high concentrations depend on the molecular weight and cationic group content of polyelectrolytes.
