Cationic surfactants

Cationic surfactants – characteristics and properties

Surfactants are amphiphilic compounds that contain both hydrophobic and hydrophilic groups, making them soluble in both organic solvents and water. Cationic surfactants are compounds that have a positively charged fragment in their structure.

The structure of cationic surfactants determines many of the functional properties that are desirable in industrial applications:

• When added to a system, they accumulate at the phase boundary and reduce surface tension, thus enabling rapid wetting of the surface.
• Interfacial action is also an important aspect of formulation stabilisation. Therefore, cationic surfactants act as emulsifiers in many mixtures.
• They have good antistatic properties. They are usually dispersed on the surface and their role is to increase surface conductivity, which helps to prevent the accumulation of surface charge.
• Cationic surfactants are used as corrosion inhibitors to protect metal materials from corrosion. The adsorption of the surfactant on metals and metal oxides creates a barrier that can inhibit corrosion.
• The dispersing action promotes the formation of fine droplets of one phase that disperse in the other phase. This reduces sedimentation and agglomeration, increasing the stability of the formulation.
• Some cationic surfactants are referred to as hydrotropes. This means that they increase the solubility of other components in the formulation.

Application of cationic surfactants

Textiles

As a component of softening formulations, cationic surfactants are used in the textile industry to give finished products antistatic and softening properties. They are also used as one of the components dedicated to fibre dyeing. Cationic surfactants reduce the stiffness, roughness and coarseness of fabrics, making them soft and fluffy.

Cosmetics and detergents

Cationic surfactants are important conditioning ingredients in hair care cosmetics such as shampoos, regenerating conditioners and hairsprays. Their primary function is to improve combability, softness and reduce static electricity. In household chemicals, they are used in concentrates and fabric softeners, where they act as softeners. In addition, they are used in the antistatic treatment of industrial fibres.

Cationic surfactants are also an important ingredient in car care products. They are found in waxes and polishes, and are also an active component in rinses designed to speed up the drying of car bodies while preventing streaks and water spots.

Plastics

Cationic surfactants are used as additives in the production of plastics, primarily due to their antistatic properties. Their use in production is very important because the phenomenon of electrical charge accumulation limits the speed of the technological process, generates material losses, causes product contamination and accelerates its decomposition. Cationic surfactants are used, among other things, in the production of polyethylene or polypropylene films.

Paper industry

In paper production, cationic surfactants are included in softening formulations. During the production process, they give the finished products antistatic properties and have a softening effect.