Abstract: | The experimental conditions for studying the electro-optical properties of a natural, modified polyelectrolyte, carboxymethylcellulose (DS 1.3; DP 180) were determined. The transient Kerr effect was found to be a function of CMC concentration, field strength, and ionic strength, I. If the concentration and I were low enough (c < 20 mg.l?1), saturation was obtained for field strengths of approximately 15 kV.cm?1. The optical anisotropy was shown to be independent of I; the electrical anisotropy decreased sharply when I increased. These results are discussed in connection with polarization theories of polyelectrolytes. The molecular dimensions of carboxymethylcellulose, calculated from the birefringence kinetics, suggest that the molecule is a rigid rod. |