Foam Stability—effect of Surfactant Composition on the Drainage of Microscopic Aqueous Films

An incident light interference microscopic technique has been employed to determine the drainage time, velocity of thinning and critical thickness of thin liquid films associated with foam systems. Using this technique, we have investigated the drainage and stability behavior of aqueous foam films of various sizes containing both single component and mixed surfactant systems. The surface tension, surface viscosity and elasticity for the surfactant solutions were also measured. The experimental results for the drainage time are compared with the theoretical predictions.