INVESTIGATION OF THIN LIQUID-FILMS OF SMALL DIAMETERS AND HIGH CAPILLARY PRESSURES BY A MINIATURIZED CELL

A highly miniaturized cell for the experimental investigation of thin foam and emulsion films has been constructed, The miniaturization of t he structure in the new design is achieved by forming the cell out of thin glass slides drilled by excimer laser and sintered into a single structure, The capillary pressures and film dimensions attainable in o ur type of cell are closer to reality than those in the currently depl oyed models, Parallel experiments on the formation and thinning of emu lsion films stabilized with nonionic surfactant (Tween 20) and with pr otein (BSA) have been carried out in the newly designed and in the con ventional cell. The data reported in the paper show that the patterns and the time scales of film evolution in the two cells are significant ly different, No dimple formation in the realistic films has been obse rved. A particularly drastic difference in the time scales is recorded in the case of protein-stabilized systems, probably resulting from th e increased interfacial viscosity and elasticity. (C) 1995 Academic Pr ess, Inc.