The Electro-Deposition of Rubber on a Zinc Anode

Abstract

Abstract 1. During the electrophoresis of rubber on a zinc anode in a weakly alkaline latex (concentration of ammonia less than 2 per cent), there is a sudden drop in the current, and as a result a diminution in the rate of deposition of the rubber. In a strongly alkaline bath, the rate of deposition remains practically constant. 2. The addition to the latex of salts the anions of which give soluble compounds with zinc diminishes to a marked degree the drop in the current strength. 3. The action of salts and alkalies is explained by the nature of the phenomenon at the anode and the structure of the film of rubber deposited. 4. The electrolytic deposition of rubber on zinc electrodes surrounded by a diaphragm of plaster or of glass takes place at a practically constant rate, irrespective of the concentration of the alkalinity in the latex. A diminution in the rapidity of the deposition of rubber still takes place upon the addition to the bath of salts the anions of which form insoluble compounds with zinc. In conclusion the authors wish to express their very deep gratitude to the Director of the Institute, Dr. L. G. Landau, for the interest which he has taken in their work.