GB527219A - An improved process for concentrating, purifying and separating colloidal dispersions or the like in the electric field - Google Patents

Abstract

527,219. Electrophoretic treatment of rubber dispersions. SEMPERIT OSTERREICHISCH-AMERIKANISCHE GUMMIWERKE AKT.-GES. March 3, 1939, No..7094. Convention date, March 10, 1938. [Class 41] In separating the disperse phase of or purifying or concentrating aqueous dispersions of rubber or rubber-like materials as described in Specifications 492,030, 505,752 and 505,753, the rate at which the particles of the disperse phase migrate towards the electrodes is increased by increasing or changing the electric charge on the particles by adding polar substances such as electrolytes, buffer solutions, emulsifying agents such as lipins, cholesterols, salts of cholic or choleic acids, or wetting- agents. In treating rubber latex, which contains negatively-charged particles, the negative charge may be increased by adding ammonia, or converted to a positive charge by adding acid or in an alkaline medium by adding cationic soap. The polar substances may be added to the liquid in the electrode compartments ; they diffuse through the diaphragm walls into the dispersion. The dispersions treated -may be those of rubber, whether vulcanized or not, guttapercha, balata, neoprene or the aqueous dispersion obtained by . polymerization of an emulsified mixture of butadiene and styrene.