Complexability of cations in anionic systems

In the mixed system of negative-cationic surfactants, rod-like micelles are easily formed after mixing with each other due to the strong electrostatic attraction between the positive and negative ions. When the concentration exceeds CMC, it will aggregate, resulting in turbidity and equal division.

Controlling the length of the hydrophobic chain, using a short-chain surfactant or adding a hydrophilic group (ethoxylation), it is possible to avoid precipitation in the solution, and the surface activity is greatly improved than that of a single component.

The synergistic effect of the combination of negative-cationic surfactants is reflected in the following points:

01

Decontamination property

Cationic surfactants can be added in a small amount to the anionic surfactant-based detergent as a synergist to improve the deconsolidation ability.

02

Solubilizing property

In the mixed system of negative and cationic surfactants, the polymerization number of the mixed micelles increases sharply with the addition of one surfactant to another surfactant with opposite charge, and the micelles transition to rod-like structure, which has greater solubilization ability for the solubilized matter soluble in the core of the micelles.

03

Foam property

There is electrical attraction between negative and cationic surfactants, and the proportional composition of the adsorption layer is necessary to achieve the maximum electrical attraction. The electrical repulsion between the adsorbed layer and the surface active ions in the micelle is weakened by the charge effect, thus increasing the surface adsorption. The above action makes the composite solution have a very low surface and interfacial tension, which will inevitably lead to an increase in foaming force. At the same time, due to the close arrangement of molecules in the adsorption layer and the strong interaction between molecules, the surface viscosity increases, the mechanical strength of the surface film increases, so that it is not easy to break under external force, the liquid loss rate in the foam is slow, the gas permeability is reduced, and the life of the foam is extended.

04

wettability

Due to the enhanced surface adsorption and low surface tension of the complex system of negative-cationic surfactants, the complex system will have a strong wetting ability.

05

Emulsifying property

The emulsifying ability of surfactants depends on their hydrophilic and lipophilic balance, the hydrophilic and lipophilic value of the oil phase and the firmness of the film formed by the surfactant at the interface of oil and water. When a small amount of cationic surfactant is added to the anionic surfactant, or vice versa, due to the effect of electric charge, the surface activity of the combined surfactant increases, and the film density formed at the oil/water interface increases, so the emulsification ability is enhanced.

In addition, the compound system can also have the advantage of two components at the same time. Cationic surfactant is a good antistatic agent and a bactericidal and mildewproof agent. It can be used as an excellent detergent for chemical fiber products by combining with anionic surfactant. It has the functions of washing, antistatic, soft and dust-proof.