In this movie we see an oil droplet (in water) that is loaded with a surfactant being drawn into a thin micropipette. In particular we use poly ethylene oxide - b - poly styrene as a surfactant, and toluene as the oil. As the drop is drawn into the pipette, its surface area changes and with a measurement of the pressure applied by the pipette a force - surface area curve can be constructed. Remember your first year physics - a force vs distance graph will get you a spring constant! In other words, we are measuring the surface modulus of the droplet. We hope that fooling around with the surfactant molecule concentration etc. will lead us to a better understanding of the molecular details of the interface.
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