Micellkonzentrasjon

Micellkonzentration refers to the specific concentration of a surfactant in a solution above which surfactant molecules begin to aggregate and form micelles. Below this critical concentration, the surfactant molecules exist primarily as individual monomers dispersed in the solvent. Surfactants are molecules that have both a hydrophilic (water-attracting) head and a hydrophobic (water-repelling) tail. In an aqueous solution, as the surfactant concentration increases, the hydrophobic tails try to escape contact with water, leading to the formation of organized structures.

The formation of micelles is a spontaneous process that occurs when the free energy of the system is minimized. Micelles are typically spherical aggregates where the hydrophobic tails are sequestered in the interior, away from the water, and the hydrophilic heads face outwards, interacting with the solvent. The exact concentration at which this aggregation begins is known as the critical micelle concentration, or CMC. The CMC is a fundamental property of a surfactant and is influenced by factors such as temperature, the presence of electrolytes, and the specific chemical structure of the surfactant. Below the CMC, surface tension decreases as more surfactant is added. Above the CMC, the surface tension remains relatively constant because the additional surfactant molecules primarily form micelles rather than further reducing the surface tension. Micelles are crucial in various applications, including detergents, drug delivery, and emulsification.