Molecular Structure Characteristics of Surfactants

Surfactants are a type of molecule with hydrophilicity and lipophilicity, which have the following molecular structural characteristics:

Hydrophilic groups: Surfactant molecules typically contain hydrophilic groups that can form hydrogen or ion bonds with water molecules, such as hydroxyl (- OH), amino (- NH2), carboxyl (- COOH), etc. These hydrophilic groups endow surfactant molecules with good water solubility and hydrophilic properties.

Hydrophobic groups: Surfactant molecules also contain hydrophobic groups such as alkyl, aromatic, or fatty acyl groups, which can bind to non-polar substances such as oils and fatty alcohols. These hydrophobic groups endow surfactant molecules with good lipophilicity and wetting properties.

Colloidal molecular morphology: Surfactant molecules typically exist in colloidal molecular morphology and can form single or multiple molecular layers to adsorb at the interface. In water, the hydrophilic groups of surfactant molecules are oriented towards water molecules; In oil, the hydrophobic groups of surfactant molecules are oriented towards the direction of oil molecules, forming a colloidal molecular structure.

Molecular length: Surfactants typically have a longer molecular length, containing 10-20 carbon atoms. Short surfactant molecules are difficult to form a stable adsorption layer at the interface, while longer surfactant molecules are prone to forming colloidal molecular structures, reflecting the properties of surfactants such as reduced surface tension and interfacial activity.

The molecular structure characteristics of surfactants directly affect their application and performance. For different application needs, suitable surfactant categories, molecular structures, and other factors can be selected to achieve the best application effect.