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2020-10-30 16:16:31
The application of surfactants in the field of disinfection has developed rapidly in recent years, and the variety and quantity of related products approved for market are increasing. In summary, alkyl glycosides are mainly manifested in four aspects: 1) direct use of surfactants with bactericidal effect, and constantly introduce new varieties; 2) adding surfactants to traditional disinfection drugs to improve and improve the disinfection effect, so as to achieve the purpose of increasing efficiency;
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2020-10-28 16:10:52
According to the different types of sealant, different industries are used. No matter what industry is used, preparation measures should be taken before use. For example, for the use of door and window sealing, the dirty things on the doors and windows should be removed first, and then used, so as to increase the sealing effect.
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2020-10-26 16:42:17
Surfactants are substances that can significantly reduce the surface tension and interfacial tension of liquids. Their molecules are composed of polar hydrophilic group and nonpolar hydrophobic group. The hydrophilic part is carboxyl group, sulfate group, sulfonic group, amine group, quaternary ammonium group and hydroxyl group, while the hydrophobic part is represented by long-chain alkanes and aromatic hydrocarbons.
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2020-10-23 15:10:24
The mechanism of biosurfactant promoting the degradation of organic pollutants and the interaction between biosurfactants and degrading bacteria and substrates are still unclear. Although biosurfactants promote microbial degradation, they also have some inhibitory factors. For example, some surfactants are toxic to microorganisms when the concentration is above CMC, and some biosurfactants colloidal particles can interfere with cell processes.
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2020-10-21 16:15:32
When the amino terminated polyether is applied, its uncured foam is sticky to the skin and clothes. Do not touch the skin and clothing when using. The pressure of 5-6kg/cm2 (25 C) in the tank can not be touched. The temperature in storage and transportation should not exceed 50 C, so as to prevent the explosion of the foam tank in the tank. We should avoid direct sunlight, and strictly prohibit the contact of the children. The used styrofoam cans should not be thrown around. Burning or piercing empty cans is prohibited. Keep away from open fire and keep away from flammable and explosive materials. The construction site of amino terminated polyether should be provided with ventilation conditions. Construction personnel should wear work gloves, work clothes and goggles during
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2020-10-19 16:11:35
In the application of flame retardant, there are also various defects. There are few flame retardant products in powder coating industry on the market, and the flame retardant mechanism is different. In order to achieve better flame retardant effect, the dosage of flame retardant is generally about 5-10%, which will cause certain damage to the coating film, and will also be greatly affected in the process of powder coating processing.
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2020-10-16 15:54:48
The flame retardancy of plastic powder polymer is very poor, which is limited in many fields. The flame retardant powder coating has the functions of flame retardant, flame retardant and heat insulation. With the rapid development of industry, the requirement of flame retardant is more and more urgent. The substances that can play the role of flame retardant are mainly the N group and halogen group elements in the periodic table of elements. The commonly used compounds are n, P, Cl, Br, Mg, Al and other elements. Economic flame retardant products such as magnesium hydroxide and other compounds, similar to this kind of products, we call them flame retardants.
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2020-10-14 15:16:02
A surfactant in which the hydrogen atoms of the hydrocarbon chain in the surfactant molecule are completely or partially replaced by fluorine atoms.
Fluorinated surfactants can be called both fluorocarbon surfactants and fluorocarbon surfactants. Their unique properties can be summarized as "three high" and "two hydrophobic", that is, high surface activity, high thermal stability and high chemical stability. Its fluoroalkyl groups are both hydrophobic and oleophobic. The unique properties of fluorine surfactants are related to the properties of fluorine atoms and carbon fluorine bonds. First of all, because fluorine is a highly electronegative element, the bond energy of C-F bond is very high. Secondly, the radius of covalently bonded fluorine atom is larger than that of hydrogen atom, which can effectively protect perfluorinated C-C bond. Therefore, fluorine surfactants have high thermal and chemical stability.
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2020-10-12 09:02:40
The molecular structure of amphoteric surfactants has hydrophobic and hydrophilic groups. The properties related to surface tension can be adjusted by changing the structure of hydrophilic part of surfactant molecule. For example, polymethylsiloxane (silicone resin) is more effective, and the unique surface activity of silicone oil is due to the hydrophobic Si - O group being shielded by hydrophilic methyl groups. Fluorinated alkyl group can further reduce the surface tension, fluorine atom has the appropriate covalent radius to shield the carbon chain from space, and the fluoroalkyl group has little interaction with other groups. Fluorosurfactants can be seen from the example of perfluorooctanoic acid [n - c7f15cooh], where the mass fraction of perfluorooctanoic acid is 0101%, the surface tension of water decreases from 72 Mn / m to 1512 Mn / m.
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2020-10-09 10:24:35
According to the flame retardant standard, phase flame retardant, also known as flame retardant, fire retardant or fire retardant, is a general term for substances that can hinder flame combustion. According to the composition, flame retardants can be divided into organic flame retardants, inorganic flame retardants and so on. Its action principle includes physical principle, chemical principle and so on. Flame retardants are widely used in building and textile materials. Flame retardant plastics are the main flame retardant products.
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2020-09-29 10:23:31
With the progress of science and technology and the improvement of living standards, polymer materials, especially synthetic polymers, such as plastics and rubber, are playing a more and more important role in people's life, and their applications are expanding year by year. However, most of the organic polymer materials have different degrees of flammability in the air. In order to realize their application in military, aerospace, transportation, power and civil industries, flame retardant modification of them has become a new topic. The ideal method of flame retardant modification of plastics is to improve the fire resistance of plastics by adding flame retardant or flame retardant masterbatch.
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2020-09-27 15:51:55
Generally speaking, organic flame retardants have good affinity. In plastics, brominated flame retardants occupy an advantage in organic flame retardant systems. Although there are many criticisms on environmental protection, it is difficult to be replaced by other flame retardant systems.
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2020-09-25 15:56:39
The cationic alkyl glucoside is stable in performance, and does not change its performance in washing liquid and washing powder to meet the requirements of processing technology, and has greater compatibility with the system. The addition of the alkyl glucoside can make the detergent foam more delicate and reduce friction, and is more suitable for the washing of fine clothes. It has no cloud point and no gel, and it can improve the water solubility and resistance of the system by adding the system.
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2020-09-23 16:33:41
According to the theory of dyeing and the physicochemical principle of surfactant, the application of surfactant as dyeing assistant in dyeing can be discussed in the following three aspects.
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2020-09-21 16:06:31
The unique properties of fluorinated surfactants are often summarized as "three high" and "two hydrophobic", that is, high surface activity, high thermal stability and high chemical stability; its fluoroalkyl groups are both hydrophobic and oleophobic.
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2020-09-18 11:15:05
The traditional fluorine-containing surfactants are mainly single chain type. At present, double chain fluorinated surfactants are attracting great interest. There are two kinds of double chain fluorocarbon surfactants reported. The first type is that the double chain is fluorocarbon chain, and the second type is double chain, which is carbon fluorine and hydrocarbon chain respectively. The latter is often called hybrid surfactants.
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2020-09-16 11:13:02
In order to prevent flocculation and sedimentation of coatings, and keep the viscosity of coatings as low as possible, so as to obtain good fluidity and coating adaptability, surfactants must be used as dispersants. In order to improve the speed of coating locomotive and save energy, it is necessary to use high solid content coatings. As a kind of surfactant with excellent performance, fluorine surfactant has little dosage and excellent effect, so it is an ideal dispersant for coatings. In order to prevent flocculation and sedimentation of coatings, and keep the viscosity of coatings as low as possible, so as to obtain good fluidity and coating adaptability, surfactants must be used as dispersants.
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2020-09-14 16:38:30
Surfactant molecules are first adsorbed on the interface between oil and solution. Under the action of lipophilic and hydrophilic groups of surfactant, plus the convection and agitation of the solution, the oil gradually separates from the metal surface and enters into the solution, forming an extremely small spherical emulsion. When the surface of the parts is strongly corroded after removing the oxide scale, various harmful gases and gases will be produced during the corrosion process When the body escapes, it produces acid fog, which has a great impact on the environment and equipment. If a small amount of OP emulsifier is added to the pickling tank, the surface of the pickling solution can produce a layer of foam to prevent the acid mist from escaping.
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2020-09-11 16:21:45
The surfactant can reduce the interfacial tension and make the wetting angle θ close to zero, and the solid powder can be spontaneously dispersed in the surfactant solution. At the same time, surfactant can help the liquid to wet the inner surface of solid, so that the liquid can penetrate into the channels and voids between the aggregates in the particles, provide a certain pressure, and under the action of mechanical force, the strengthening bond force of particle aggregates is destroyed. At the same time, surfactants can help to grind, reduce the surface energy of particles, prevent the surface of the damaged surface from bonding, so as to prevent particles from coalescence.
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2020-09-09 15:49:40
The main reaction in the synthesis of cationic surfactants is N-alkylation, in which tertiary amine reacts with alkylation reagent to form quaternary ammonium salt, which is also called quaternization reaction.
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