Foaming agent Foaming agent A foaming agent is a material that facilitates formation of foam such as a surfactant or a blowing agent. A surfactant, when present in small amounts, reduces surface tension of a liquid (reduces the work needed to create the foam) or increases its colloidal stability by inhibiting coalescence of bubbles. A blowing agent is a gas that forms the gaseous part of the foam. Sodium laureth sulfate, or sodium lauryl ether sulfate (SLES), is a detergent and surfactant found in many personal care products (soaps, shampoos, toothpastes, etc.). It is an inexpensive and effective foamer. Sodium lauryl sulfate
Surface tension entropy, energy and free energy. As stated above, the mechanical work needed to increase a surface area "A" is . Hence at constant temperature and pressure, surface tension equals Gibbs free energy per surface area: where is Gibbs free energy and is the area. Thermodynamics requires that all spontaneous changes of state are accompanied by a decrease in Gibbs free energy. From this it is easy to understand why decreasing the surface area of a mass of liquid is always spontaneous (), provided it is not coupled to any other energy changes. It follows that in order to increase surface