surfaktante

Surfaktante is a term used for substances that reduce the surface or interfacial tension between liquids, gases, or solids. They are amphiphilic molecules, having a hydrophobic tail and a hydrophilic head, which drives their adsorption at interfaces and the formation of structures such as micelles in solution. By accumulating at interfaces, surfaktantes improve wetting, spreading, emulsification, solubilization, and foaming.

Surfactantes are commonly categorized by the charge of their hydrophilic head: anionic, cationic, nonionic, and zwitterionic. Examples include alkyl sulfates and sulfonates (anionic), quaternary ammonium compounds (cationic), nonionic ethoxylated or glycol-based surfactants, and zwitterionic betaines. They can be synthesized from petrochemical feedstocks or derived from renewable sources, such as fatty alcohols or sugars. Biosurfactants produced by microorganisms are another important subgroup.

Key concepts in surfaktante science include the critical micelle concentration (CMC), the concentration above which micelles form and active solubilization of hydrophobic substances occurs. The choice of surfaktante depends on application, required properties (foaming, detergency, emulsification, or stabilization), cost, and environmental considerations.

Applications span detergents and cleaners, personal care products, cosmetics, food industry as emulsifiers and stabilizers, pharmaceuticals, agrochemicals, and industrial processes such as enhanced oil recovery and polymerization. In cleaning and formulation, surfaktantes reduce soil-surface adhesion and promote soil dispersion in water.

Environmental and health impacts vary with structure; many modern surfaktantes are designed to be biodegradable and of low toxicity, though some can affect aquatic ecosystems. Regulation often covers labeling, usage, and disposal in many regions.