Influence of Foaming Gas on Foam Stability

Abstract

As part of a study of those factors which influence the stability of foams used in the processing of textiles, foams were generated using six different gases. The stabilities of the foams were estimated by measuring the change in foam viscosity as a function of time. The data are consistent with the hypothesis that the flow of gas through the bubble walls is an activated diffusion process where the permeation rate of the gas is proportional to the solubility of the gas in the liquid phase and to the molecular size of the gas. The redistribution of bubble sizes as a result of gas permeation between bubbles leads to bubble growth and to a decrease in the foam viscosity.