Water-soluble polymer adsorption surfactant
Water-soluble macromolecule adsorbed surfactants reduce the number of free surfactant molecules in solution, and the critical micelle concentration increases; cationic surfactants and water-soluble macromolecules containing carboxyl groups generate insoluble complex condensate; however, in solutions containing macromolecules, once micelles are formed, their solubilizing effect is significantly increased.

Homologous mixed system
The CMC of the mixed system is not linearly related to the molar fraction of each component, nor is it equal to the simple sum average; the surface activity of the two homologues mixed system in equal amounts is between their respective surface activities, and it tends to be more active (i.e., the carbon chain is longer) components, which have a greater influence on the CMC than the sub-sub-sub-sub-sub-sub-sub-sub-sub-sub-sub-sub-sub-sub-sub-sub-sub-sub-sub-sub-sub-sub-sub-sub-sub.
Mixed systems of nonionic and ionic surfactants
The two are more likely to form mixed micelles, with CMCs between the two surfactant CMCs or lower than the CMC of either surfactant; for anionic surfactant-polyoxyethylene-based nonionic surfactant systems, stronger synergistic effects may occur when the number of polyoxides is increased, but electrolytes may diminish the synergistic effects.
Cationic surfactant-anionic surfactant mixture system
The degree of effectiveness of surfactant mixtures is related to the mixing ratio of the two and the length of the hydrocarbon chain, the closer the hydrocarbon chain length and the longer the hydrocarbon chain, the stronger the solubilization effect; in the aqueous solution, the appropriate pairing of ionic surfactants with opposite charge can form a molecular complex with high surface activity, which has an effect on wetting, solubilizing, foaming, sterilization, etc.; however, if the mixing ratio is not appropriate and the mixing method is not suitable, it can lead to solubility and solubility. However, if the mixing ratio is not appropriate, mixing method is not suitable, it can lead to the precipitation of ionic compounds with small solubility from the solution.

Emulsifiers (surfactants or surfactants) are toxic?
This is a very typical amphiphile, the round end is hydrophilic, and the zigzag end is lipophilic. In fact, such substances exist in nature, for example, phospholipid, lecithin, saponin, or glycolipid, etc. There are quite a lot of them. There are a lot of them, you can Google “natural surfactants” or “natural surfactants”, so surfactants are not a synthetic substance created out of thin air, which can cause ionic compounds with very low solubility to precipitate from the solution.

Due to the characteristics of surfactants being both lipophilic and hydrophilic, it was soon discovered by human beings that they can be used to solve the problem of oil-water incompatibility, the most common one being the addition of egg yolks to salad dressing, which turns the original oil-water incompatible liquid into a cream, in which the emulsifier is the lecithin in the yolks, and human beings have also found out that the sap of some plants will foam when mixed with water. And human beings also found that some plant sap, used to mix with water will foam, can clean dirt, the reason is that these plant sap contains plant saponin, can be used as a natural surfactant for cleaning, and even human beings also inadvertently found that you can synthesize their own surfactants can be used to wash and clean, can also be used as an emulsifier to emulsify the oil and water, to produce cream to be applied to the skin, to play a moisturizing effect to protect the skin (the former soap, the latter is a cream). the latter is snow cream).

Translated with DeepL.com (free version)