The surfactant is basically unchanged in the reaction process and can be reused. And its dosage is very small, but how small is appropriate, still need to be determined by experiment according to different conditions. For example, in the production of poly (2,5-dibutyloxy-p-phenylacetylene), the yield of the product first increases and then decreases with the increase of the amount of active agent. This is because the active monomer formed in the aqueous phase is transferred to the organic phase by virtue of the action of PTC to participate in the polymerization. Therefore, the initial yield increases with the increase of PTC dosage When the amount of PTC exceeds a certain limit, the concentration of the system increases and is very viscous, which is not conducive to the monomer transfer reaction, resulting in the decrease of polymerization yield.

Asphalt emulsifier is a kind of surfactant. Emulsifier and detergent have the same adsorption, orientation, colloidal ion formation and reducing interfacial tension. However, as an emulsifier, it also needs film-forming property, especially for asphalt emulsifier, it needs appropriate carbon chain alkanes to better emulsify with asphalt. Fig. 2 shows the properties and characteristics of surfactant From the diagram, we can see the relationship between the basic properties of various surfactants including emulsifiers and their use up to now.

The metabolic process of fermentation material is a series of biochemical reactions. Due to the small size of bacteria, the rapid biocatalytic reaction, the difficulty of reaction tracking and the limitation of experimental equipment, the development of basic research on microbial material metabolism has been restricted to a great extent. It takes quite a long time to completely understand the material metabolism process of a strain For example, the research of glutamic acid fermentation

As the key raw material of spray polyurea elastomer, the elastomer made from amino terminated polyether has excellent tensile strength, elongation, wear resistance, aging resistance, corrosion resistance and tear resistance. This component can make spray polyurea have excellent construction performance and environmental protection performance, so it is widely used in the protection of concrete, steel structure and other materials.

Alkyl glucoside is a new type of nonionic surfactant. Compared with other surfactants, it has the characteristics of stability, non toxicity, solubility, biodegradability and low irritation to skin. Advantages: high surface activity, high viscosity, rich foam, fine and stable. It has obvious synergistic effect with other surfactants, so it can be used as detergent, detergent, cosmetic surfactants, pharmaceutical additives and industrial emulsifiers.

The zeta potential curve showed that when aeo-7 concentration increased from 0 to 0.1 mol / L, zeta potential changed from - 37.9 MV to - 16.3 MV. Because the nonionic surfactant has no charge, its adsorption on the surface of carbon black particles will not cause the change of its charge, but the negative charge of carbon black particle surface decreases after adding aeo-7.

The coagulation effect of surfactant is related to the type and dosage of surfactant, the degree of water pollution, pH value and other factors. The dosage of surfactant is very important to the coagulation effect when other conditions are unchanged. The dispersion and condensation of solid particles in water are a pair of contradictions. For surfactants, due to the characteristics of their molecular structure, they have both dispersing and condensing effects. Generally speaking, when the density of solid particles in water is large, adding a small amount of surfactant can play a role of coagulation. If the solid particle density exceeds a certain amount, it can not agglomerate but disperse.

It is also very important to select the appropriate amount of surfactant in the control of particle size, particle size distribution, particle shape and so on. Too much or too small amount of surfactant will affect the properties of nano ZnO to a certain extent.

The application of surfactants in building materials, with the development of domestic construction industry, more and more chemical technology has been introduced into the production process of building materials, and surfactant has become one of the important chemical raw materials. According to the current research on the application and development of surfactants in the construction industry, we found that surfactants mainly play an important role in the application of magnesite building materials and water-based building coatings.

The principle of surfactant oxygenation: adding surfactant to aquaculture water can increase the saturation solubility of oxygen in aquaculture water. According to hydrate formation theory and double membrane theory, because the solubility of oxygen in water is very small, water oxygenate usually forms at the gas-liquid interface, and then slowly diffuses from the gas phase to the liquid phase. In the water containing surfactant, due to the solubilization of surfactant, a large amount of oxygen is dissolved in the surfactant micelles formed in the aqueous solution. Thus, the formation of water oxygenates in the surfactant aqueous solution can occur not only at the gas-liquid interface, but also within the water body, which reduces the formation time of water oxygenates and improves the oxygen content in water Solubility in.   

The surface tension and surface energy can be reduced by adding surfactant to the precursor of nano materials, so as to reduce the aggregation degree of solid or liquid particles in the dispersion system, keep the dispersion system relatively stable, and effectively regulate the size and morphology of nanoparticles.

Surfactants have lipophilic and hydrophilic groups, which are amphiphilic molecules. Water is a strong polar liquid. When surfactant is dissolved in water, according to the principle of similar polarity and opposite polarity, its hydrophilic group and water phase attract and dissolve in water, while its oleophilic group repels water and leaves water. As a result, surfactant molecules (or ions) are adsorbed on the interface of two phases, which reduces the interfacial tension between the two phases. The more adsorption of surfactant molecules (or ions) on the interface, the greater the reduction of interfacial tension.

Polyether amine in the use, need special attention, we must ensure the quality of the product, ensure its purity, not mixed by other substances, so we must pay attention to the following matters when using this kind of curing agent, so that we can better ensure the use effect of the product.

The selection of suitable surface modifier plays a decisive role in the preparation of nano ZnO. The application purpose and requirements of the treated object, particle size, particle size distribution, particle morphology, surface polarity and treatment process must be considered before use.

The different degree of polymerization of the same surfactant has a great influence on the size and dispersion of ZnO nanoparticles. Wu Wei et al. Studied the effect of PEG with different molecular weight on the size and dispersion of ZnO nanoparticles. The results show that nano ZnO modified by PEG in situ can disperse Zn (OH) 2 by adsorbing on the surface of Zn (OH) 2 precursor and depending on the steric hindrance effect produced by the long chain structure of PEG. If the molecular weight of PEG is too small, it can not play the role of steric hindrance. If the molecular weight of PEG is too large, the intermolecular force between particles will be enhanced and agglomeration will occur.

The development potential of flame retardants in the domestic market is still huge. With the further improvement and implementation of fire prevention and flame retardant laws and regulations in China and other emerging markets, the application areas and demand scale of flame retardants will be further expanded.

In the process of surfactant promoted bioremediation, different types of surfactants will get different remediation results due to their different characteristics, and if the critical micelle concentration is not reached, the surfactant has no solubilization effect. If the concentration is too high, it may inhibit the microbial degradation. Therefore, in the actual remediation of soil, surfactant with good type and concentration should be used.  

When the surfactant is added into the liquid, even if the concentration is very small, it will spontaneously cause a strong reduction of the surface or interfacial tension. Surfactants are amphoteric in structure. One end of the surfactant is hydrophilic and the other is hydrophobic. The amphoteric molecules will self orientate on the surface of the solution, the polar groups extend to the water, while the hydrophobic hydrocarbon groups extend to the air or oil interface, thus reducing the surface tension of the liquid. Surfactants can emulsify, disperse, solubilize, moisten, foaming, defoaming, lubricating, washing, softening, antistatic and anti-corrosion.

Biosurfactants are the rising star in the surfactant family. They are a kind of biological macromolecular substances with surface activity produced by microorganisms. Most of them are produced by bacteria, yeasts, fungi (molds). Biosurfactants produced by microorganisms can be divided into five categories according to their chemical composition and microbial sources, including glycolipids, fats, polysaccharide protein complexes, phospholipids and fatty acids or neutral lipids. Many microorganisms can secrete biosurfactants (see Table 1). Most biosurfactants are anionic, and their CMC is usually in the range of 1-200 mg / L, and its molecular weight ranges from 500 to 1500 da. A kind of

In the process of surfactant promoted bioremediation, different types of surfactants will get different remediation results due to their different characteristics, and if the critical micelle concentration is not reached, the surfactant has no solubilization effect. If the concentration is too high, it may inhibit the microbial degradation. Therefore, in the actual remediation of soil, surfactant with good type and concentration should be used.