Uses of Surfactants
Surfactants are extremely versatile and their applications permeate almost all industrial fields, and it is difficult to find an industry that has nothing to do with surfactants. In many industries, surfactants play the role of the finishing touch, as important auxiliaries can often greatly improve the production process and product performance. It is not an exaggeration to say that surfactants are the most important chemical industry additives today, and are therefore called “industrial MSG”.
Industrial surfactants can be divided into two main categories. One is industrial cleaning, for example, trains, ships and other transportation, machines and parts, electronic instruments, printing equipment, oil storage tanks, nuclear contaminants, boilers, down products, food cleaning.
According to the nature and characteristics of the items to be washed and a variety of formulations, which mainly use surfactant emulsification, solubilization, wetting, penetration, dispersion and other properties supplemented by other organic or inorganic additives, to achieve the cleaning and removal of oil stains and rust, sterilization and protection of the surface layer of the purpose.
Another type is to use the derived properties of surfactants as industrial auxiliaries, such as lubrication, softening, catalytic, bactericidal, antistatic, plasticizing, defoaming, deodorizing, thickening, coagulant reduction, rust prevention, waterproofing, oil repellent, anti-caking, flotation, phase transfer catalysis, etc., which are used in the electronic industry, bionanomaterials, polymerization, genetic engineering, biotechnology, etc., and there are many other applications under continuous development.
Industrial surfactants in addition to general anionic, nonionic, cationic, amphoteric surfactants, in order to meet the needs of synthetic rubber, synthetic resins, coatings production in the emulsion polymerization, but also the development of functional surfactants, such as reactive surfactants; can be dissociated surfactants, containing silicon, fluorine, boron, and other special surfactants, etc., are widely used in textile printing and dyeing, chemical fiber industry, petroleum mining, building materials, metallurgy, transportation, manufacturing, and other specialties. building materials, metallurgy, transportation, papermaking, water treatment, pesticide emulsification, fertilizer anti-caking, oil field chemicals, food, film, pharmaceuticals, leather and national defense and other fields.
The main uses of different types of surfactants.
(1) Anionic type Anionic carboxylate type surfactants, if the salt is soluble alkali metal soap, mainly used as detergents, cosmetics and so on. If the salt is insoluble soap, such as calcium carboxylate, lead carboxylate, manganese carboxylate, etc., it can be dissolved in organic solvents, and is often used as paint drying agent, anti-caking agent, etc. There are also polycarboxylic acid soap, lead carboxylate, manganese carboxylate, etc., which can be used as organic solvents. There are also polycarboxylic acid soap, rosin soap, N-acylamino carboxylic acid soap, is used as emulsifiers, detergents, lubricants, additives, anti-marketing agents.
Anion for the sulfate salt surfactants, due to the chemical structure of the hydrophobic base is different, and its properties are different, such as senior alcohol sulfate salt has a good washing power, emulsifying power, foam, easy biodegradation, its water solubility and decontamination power than soap, and solution is neutral, does not damage the fabric, in hard water is not easy to precipitate, is widely used in household and industrial detergents, shampoos, cosmetics and other collar city.
Sulfated olefins, sulfated oil, sulfated fatty acid esters, etc., due to the presence of branched chains in the water-repellent base, its penetration and wetting power is good, but the detergency is poor, and it is mostly used as fiber printing and dyeing auxiliaries.
Sulfonate-type anionic surfactants, such as alkylbenzene sulfonate, alkyl sulfonate, a-olefin sulfonate, have good detergent detergency and are widely incorporated into the formulations of laundry detergents and liquid detergents.
In short, anionic surfactants, if they are water-soluble and the hydrophobic group is straight-chained, are mainly used as detergents and cleaning agents and are widely used in the washing industry. If the hydrophobic group is branched chain type, it is used as penetrating agent, wetting agent and fiber printing and dyeing auxiliary.
(2) Cationic type Cationic surfactants are rarely used as cleaning agents. The reason is that many of the washed substrate surface with a negative charge, positively charged cationic surfactants do not dissolve dirt, but is adsorbed on the surface of the substrate. And this property can be used as antistatic agent, softener of fiber, trapping agent or flotation agent in mineral processing, corrosion inhibitor of metal products, etc..
Due to fatty amines and quaternary ammonium salts can be tightly oriented in the bacterial semi-permeable membrane and water or air interface, hindering the organism’s respiration or cut off the source of nutrients resulting in bacterial death, so the cationic surfactants can be used for antimicrobial and bacteriostatic, quaternary ammonium salts containing benzyl is recognized as an effective bactericidal agent.
(3) Amphoteric type Amphoteric surfactants have many excellent properties: good decontamination, foaming and emulsification ability, hard water, acid and alkali and a variety of metal ions have a strong ability to tolerate, low toxicity and skin irritation, good biodegradability, and has a special performance of antistatic and sterilization. It is widely used in the fields of anti-static, fiber softening, special detergents as well as shampoos and cosmetics. Its application range is expanding.
(4) Nonionic The water solubility of nonionic surfactants follows the hydrophilic hydroxyl group
