Studies on the aggregation of dyes in aqueo us solutions

Abstract

The aggregation behaviour of the dyes Chlorazol Sky Blue FF, Chrysophenine G, Benzopurpurine 4B, Congo Red, Orange II and Methylene Blue in aqueous solutions has been studied polarographically at 30° and 40°C, in the presence of sodium chloride and potassium chloride at concentrations ranging from 0.025 M to 0.2M. In the case of Chlorazol Sky Blue FF, Chrysophenine G, Orange II and Methylene Blue it was found that the aggregation prodeeded only to the dimerisation stage under these conditions. The dyestuffs Congo Red and Benzopurpurine 4B on the other hand were highly aggregated and the degree of aggregation was strongly temperature sensitive.