Surfactant is a collective term for substances with hydrophilic and hydrophobic groups. Such substances are alson known as amphiphilic substances. When we dissolve a surfactant in water, the hydrophobic groups are surrounded by water molecules and become unstable above certain concentrations. Seeking stability, the surfactant molecules gather in flocs, formng micelles with hydrophilic groups oriented outward and hydrophobic groups oriented inward. This state is known as the critical micelle concnetration (CMC).
We measured particle diameters of micelles of sodium dodecyl sulfate (SDS) and the nonionic surfactant Tween 20 in pure water.
