Surfactants (surfactants).

In 1917, the American I. Langmuir discovered that some substances accumulate very actively on various boundary surfaces (at the boundaries of air - water, water - oil). Accumulation occurs because the surface of any body has an uncompensated supply of free energy, which arises because the molecules solid or liquids are attracted to each other with a force many tens of times greater than air molecules. As a result, at the solid-air interface there appears a layer of molecules whose attractive forces are not compensated. This is the reason for the excess free energy and surface tension at the solid-air interface.

The addition of substances of different chemical nature leads to an increase or decrease in the surface tension of aqueous solutions. Substances that increase surface tension are called surface-inactive (PIAV) ; downgrading – surfactants . PIAVs include, for example, any electrolytes (alkalis, acids). Surfactants are most often bipolar organic compounds, the nonpolar (hydrophobic) part of which is represented by a long-chain hydrocarbon radical with C › 8, the polar (hydrophilic) part is represented by various functional groups.

When a surfactant comes into contact with the surface of a liquid or solid, a process occurs adsorption , which consists in the accumulation of surfactant molecules at the interface. A special feature of adsorption is that it occurs with the release of heat, not on the entire surface of the solid, but only on its active centers. The adsorption layer may consist of one or more layers of adsorbed molecules. A feature of the liquid surface is that all its points are equally active for adsorption. The hydrophilic group of the surfactant is directed towards water, and the hydrophobic group - towards air. Langmuir called this orientation of molecules a “picket fence.” As a result, the properties of bodies coated with adsorption layers change dramatically: hydrophobic surfaces become more hydrophilic, they are better wetted by water.

During adsorption, the surfactant also dissolves in one of the phases. In this case, true solutions are first formed, in which the surfactants are in the form of molecules. As surfactants are added, a sharp change in the properties of the solutions is observed. The formation of colloidal solutions occurs in which surfactants are present in the form of larger aggregates called micelles. The limit of true solubility of a surfactant is called the critical micelle concentration (CMC).

Most universal methods KKM definitions are:

1) calculation from surface tension isotherms of surfactant solutions;

2) potentiometric titration of surfactant solutions;

3) temperature method (based on the Kraft point of surfactant solutions).

The ability of a surfactant, when adsorbed on a phase interface, to radically change its properties and thereby influence many important parameters of disperse systems is widely used in a variety of fields of technology and numerous technological processes. In this case, the influence of surfactants can be different depending on the chemical nature and structure of the adjacent phases and surfactant molecules, as well as on the conditions of their use. According to Rebinder, four groups of surfactants can be distinguished:

a) according to the physico-chemical mechanism of their effect on the phase interface and the dispersed system as a whole:

· substances that are surfactants only (or predominantly) at the water-air interface.

Surfactants belonging to this group are moderately active wetting agents and foaming agents. Some representatives (octanol, isoamyl alcohol) can act as defoamers;

· substances of various natures, surfactants at various interfaces between condensed phases. Surfactants of this group most often act as dispersants; in addition, they allow you to manage electoral m;

· Surfactants that have the ability to form gel-like structures in adsorption layers and in phase volumes.

As a rule, these are high-molecular surfactants (proteins, glycosides, cellulose derivatives, etc.). Such substances are used as highly effective stabilizers of moderately concentrated disperse systems of various natures: foams, emulsions, suspensions. Surfactants of this group can act as plasticizers for highly concentrated dispersions;

· Surfactants with a detergent effect.

They combine the functions of the surfactants of the rest three groups and, in addition, are capable of forming thermodynamically stable colloidal particles in the volume of the liquid phase - micelles and inclusion of washable contaminants into the core of micelles – solubilization . An important quantitative characteristic of a surfactant is hydrophilic-lipophilic balance (HLB) G Riffin - Davis. HLB numbers characterize the relationship between hydrophilic and hydrophobic properties: the higher the HLB number, the more the balance is shifted towards the polar (hydrophilic) properties of the surfactant. HLB numbers are determined experimentally. Davis's work established the quantitative dependence of HLB on the composition and structure of the surfactant. Each structural unit contributes to the number of HLB. GLB numbers according to Griffin are:

o for hydrophilic groups: -COOC – 21.1, -COONa – 19.1, -COOH – 2.4, -OH – 1.9, =O – 1.3, -SO3K – 38.7, -SO3H – 3.8;

o hydrophobic: =CH-, -CH2-, -CH3, =C=C- -0.475; o = -1.25

Based on these data, HLB numbers can be calculated using the formula:

Where Σ(HLB G.PHIL.) and Σ(HLB G.FOB.) is the sum of the HLB numbers of all hydrophilic and hydrophobic groups, respectively.

The physical meaning of HLB numbers is that they determine the work of adsorption during the transfer of polar groups of surfactant molecules into the nonpolar phase and nonpolar groups into the polar phase. Depending on the number of HLB, surfactants are used for one purpose or another. Thus, if surfactants have HLB numbers from 7 to 9, they are used as wetting agents, from 13 to 15 - as detergents, from 15 to 18 - as solubilizers in aqueous solutions;

b) Based on their chemical structure, surfactants are divided into two large classes.

These are, on the one hand, organic surfactants with amphiphilic molecules, universally surfactant at most interphase boundaries, but providing only a slight (30–40 mJ/m2) decrease in surface tension. On the other hand, these are the most diverse, first of all inorganic substances, exhibiting selective, but often very high surface activity in relation to this particular interface, capable of causing a very sharp decrease in surface tension (for example, sodium phosphates in aqueous systems);

c) by type of raw material, used for synthesis, surfactants are divided into natural and synthetic;

d) by chemical nature and charge sign, acquired by the surface during adsorption, surfactants are classified into anionic, cationic, nonionic, amphoteric.

In the production of ISC, in addition to binders, aggregates and fillers, additives in mixtures called additives are widely used.

At the stages of technological production they:

- facilitate operations;

Reduce the amount of energy expended;

Reduce consumption of expensive components;

Reduce material consumption;

Help ensure the necessary indicators of material properties;

Favor the acceleration or slowdown of the processes of structure formation and hardening.

At the stage of operation of structures, the additives introduced earlier by ISK are designed to:

Strengthen and stabilize the structure of the material;

Maximum inhibition of the inevitable destruction that arises and develops in the material under the influence external environment and internal spontaneous phenomena.

The main functional purpose of additives is and this is how they differ from fillers and fillers, is that that they always interact quite actively with one or more components of mixtures in the process of forming the structure of the binder part or the macrostructure of the ISC. As a result of the reaction, new compounds appear that were not previously in the mixture, and the additives are either completely consumed or lose their individual characteristics. It is clear that if the amount is excessive, the additives may partially remain in the mixture and in the formed material without any changes, which is not desirable.

Surfactants (Surfactant ) are those chemical compounds that are adsorbed on the interfaces of liquids and solids and affect their physicochemical or Chemical properties. Surfactants are, as a rule, compounds whose molecules consist of two main parts - a radical and a functional group.

Radical- is a group of atoms that is unchanged during a number of chemical transformations and passes from the molecule of one compound to the molecule of another.

Radicals are formed, for example, when organic compounds of hydrogen atoms are removed from hydrocarbon molecules. Thus, if in any saturated (saturated) compound belonging to the class of paraffins such as C n H 2 n +2, a hydrogen atom is eliminated, then the remaining group of atoms C n H 2 n +1 is an aliphatic (fatty) radical

N - C - C - ... - C -, which is designated by the letter R.

The place of the abstracted hydrogen in the molecule can be taken by another atom or group of atoms with certain properties, associated with the stationary displacement of electrons in atomic orbits, which determines the presence of a certain electric dipole and dipole moment of the entire molecule. Such atoms or groups of atoms are called functional groups .

The most common functional groups found in surfactants are:

Hydroxyl: (- OH);

Carboxyl: (- COOH);

Amine (amino group): (- NH 2);

Nitro group: (- NO 2);

Sulfate group: (- SO 3 H).

Depending on the number of functional groups in the molecule, surfactants can be one-, two-, or polybasic.

Compounds in which the aliphatic radical contains less than 10 carbon atoms, as a rule, do not have surface activity, i.e. the ability to adsorb and reduce the surface tension of liquids or the surface energy of solids. When a radical contains more than 10 carbon atoms, they are usually surface active and are called higher fatty surfactants . The solubility of surfactants in various solvents and the ability to dissociate into ions depend on the type of functional polar group and the structure of the radical.

Surfactants in which the functional groups carry a positive charge are active in an acidic environment and inactive in an alkaline environment, while surfactants with negatively charged functional groups, on the contrary, are active in an alkaline environment and inactive in an acidic environment.

CLASSIFICATION OF SURFACTANTS

Fundamentally, all surfactants are divided into two large groups: inogenic compounds that dissociate into ions when dissolved in water, and non-inogenic compounds that do not dissociate into ions.

Depending on what ions are responsible for the surface activity of ionic substances - anions or cations, ionic substances are divided into anionic, cationic, ampholytic. Anionic surfactants are active in alkaline solutions, cationic surfactants are active in acidic solutions, and ampholytic surfactants are active in both.

Anionic substances in alkaline solutions, forming negatively charged surface-active ions (anions):

RCOONa ↔ RCOO - + Na +

Cationic substances, when dissociated in acidic solutions, form positively charged surface-active ions (cations):

RNH 3 Cl ↔ RNH 3 + + Cl -

Anionic surfactants include: carboxylic acids (RCOOH) and their salts (RCOOMe), etc.

Cationic surfactants include amines and ammonium bases:

RNH 2; RNH 3 Cl.

Ampholytic surfactants contain two functional groups, one of which is acidic and the other is basic, such as a carboxyl and an amine group.

Depending on the environment, ampholytic compounds have anionic or cationic properties:

Alkaline environment is acidic environment;

RNH(СH 2) n COO - ↔ RNH(СH 2) n COOH↔RNH 2 (СH 2) n COOH;

Anionic properties cationic properties.

Nonionic surfactants, when dissolved in water, do not form ions.

The group of non-iogenic surfactants includes products of oxyethylation of fatty acids, alcohols, and amines.

RCOO(C 2 H 4 O) n · H ; RCH 2 O(C 2 H 4 O) n H; RC 6 H 5 O(C 2 H 4 O) n OH.

CLASSIFICATION OF PASTERACTIVES BY MECHANISM OF ACTION

Depending on the action of surfactants in dispersed systems, they are divided into 4 groups:

To the first group These include low-molecular, truly water-soluble surfactants, such as alcohols. They are weak wetting agents and defoamers.

To the second group include surfactants, dispersants and emulsifiers. By being adsorbed, they effectively reduce the free surface energy of a liquid or solid and thereby facilitate the process of formation of new surfaces and dispersion. These substances also have some stabilizing effects.

As a result of oriented adsorption, surfactants of the second group hydrophobize solid surfaces and, conversely, hydrophilize hydrophobic surfaces. The effect of hydrophobization of these surfactants is especially pronounced, which is enhanced by chemical bonding - the fixation of the polar groups of the surfactant on the corresponding areas of the solid surface.

The surfactants of the second class include fatty acids, their water-soluble salts, cationic organic bases and salts.

To the third group Surfactants that are good stabilizers are combined. Their surface activity is relatively low.

These surfactants are also good adsorption plasticizers - they plasticize the structure, reducing their strength and structural viscosity. In cement mortars and concretes, this allows the transition to rigid and at the same time homogeneous mixtures, promotes uniform mixing, increases density and durability (frost resistance), leads to increased strength and reduced cement consumption.

Calcium lignosulfonates (sulfite-alcohol stillage - SSB and sulfite-yeast mash - SDB), etc. are used as plasticizers.

Fourth group of surfactants- These are detergents with high surface activity, wetting and water-repellent effects. They are also effective emulsifiers and emulsion stabilizers. This group includes soaps of fatty acids and amines.

In construction, surfactants of the second and fourth groups are mainly used.

Surfactants for cement concrete mixtures and cement concrete are divided into the following types:

1. Regulating properties of concrete mixtures

1.1. Plasticizing groups 1-4 (super-, strong-, medium- and low-plasticizing). They increase the mobility of the concrete mixture, slow down the setting of concrete and increase strength.

1.2. Stabilizing. They increase the homogeneity of concrete and reduce permeability.

1.3. Water-retaining. They increase the mobility of the mixture, reduce the permeability and strength of concrete, and increase the homogeneity of concrete.

1.4. Improving pumpability. They increase homogeneity, reduce water separation of the mixture and reduce the strength of concrete.

1.5. Retarding setting. They increase the mobility time of the mixture, slow down setting by 2 or more times at +20°C. Increased strength over long curing periods.

1.6. Accelerating setting. Accelerate setting by 20% or more at 20°C. Acceleration of hardening.

1.7. Porosizing - for lightweight concrete.

1.8. Air-entraining. Increased workability and frost resistance, reduced delamination.

1.9. Foam- and gas-forming. Foaming additives provide technical foam. Gas-forming surfactants are capable of releasing gas due to chemical interaction with cement hydration products.

2. Controlling concrete hardening

2.1. Accelerating hardening. Increase in strength at the age of 1 day by 20% or more. Slowing down of strength gain at a later date.

2.2 Retarding hardening. Reduction in concrete strength by 30% or more at the age of up to 7 days.

3. Increasing strength and (or) corrosion resistance, frost resistance of concrete, reducing concrete permeability

3.1. Water-reducing (groups 1-4). Reduced water consumption (20-5%). Increased frost resistance and corrosion resistance.

3.2. Colmatizing. Increasing the grade of concrete for water resistance and corrosion resistance.

3.3. Air-entraining and gas-forming. Increased frost resistance by 2 or more times, plasticization of the mixture.

3.4. Increasing the protective properties of concrete in relation to reinforcement (steel corrosion inhibitors). Increasing the mobility of the mixture and reducing the diffusion permeability of concrete.

4. Giving concrete special properties

4.1. Antifreeze (providing hardening at subzero temperatures).

4.2. Hydrophobizing (1-3 groups). Reducing water absorption by 1.5-5 times or more, slowing down setting.

The introduction of surfactants into cement paste, mortar or concrete mixture significantly changes their structure and properties in both plastic and hardened states. Different kinds The surfactants noted above change the properties of the concrete mixture or concrete in different ways due to their adsorption on the surface of clinker grains and new formations, as well as the surface of stone materials.

The microstructure of hydrated cement also changes as a result of developing adsorption modification. The surface of the crystals formed in cement paste and stone is covered with an adsorption passivating film of surfactants, crystal growth slows down and a smaller crystalline structure is formed with a change in the very shape of the crystals.

Thus, by using surfactants, it is possible to significantly expand the possibilities for the production of asphalt and cement concrete mixtures. In this case, the main thing is making the right choice materials and additives, as well as their dosage.

Surfactants have a polar (asymmetric) molecular structure, are able to be adsorbed at the interface of two media and reduce the free surface energy of the system. Quite insignificant additions of surfactants can change the properties of the particle surface and give the material new qualities. The action of surfactants is based on the phenomenon of adsorption, which simultaneously leads to one or two opposite effects: a decrease in the interaction between particles and stabilization of the interface between them due to the formation of an interphase layer. Most surfactants are characterized by a linear structure of molecules, the length of which significantly exceeds the transverse dimensions (Fig. 15). Molecular radicals consist of groups that are related in their properties to solvent molecules, and of functional groups with properties that are sharply different from them. These are polar hydrophilic groups, having pronounced valence bonds and having a certain effect on wetting, lubricating and other actions associated with the concept of surface activity . At the same time, the supply of free energy decreases with the release of heat as a result of adsorption. Hydrophilic groups at the ends of hydrocarbon non-polar chains can be hydroxyl - OH, carboxyl - COOH, amino - NH 2, sulfo - SO and other strongly interacting groups. Functional groups are hydrophobic hydrocarbon radicals characterized by side valence bonds. Hydrophobic interactions exist independently of intermolecular forces, being an additional factor that promotes the approaching, “sticking together” of non-polar groups or molecules. The adsorption monomolecular layer of surfactant molecules is oriented with the free ends of the hydrocarbon chains away from

surface of the particles and makes it non-wettable, hydrophobic.

The effectiveness of a particular surfactant additive depends on physical and chemical properties material. A surfactant that produces an effect in one chemical system may have no effect or a clearly opposite effect in another. In this case, the surfactant concentration is very important, determining the degree of saturation of the adsorption layer. Sometimes high molecular weight compounds exhibit an effect similar to surfactants, although they do not change the surface tension of water, for example polyvinyl alcohol, cellulose derivatives, starch and even biopolymers (protein compounds). The effect of surfactants can be exerted by electrolytes and substances insoluble in water. Therefore, it is very difficult to define the concept of “surfactant”. In a broad sense, this concept refers to any substance that is not large quantities ah significantly changes the surface properties of the dispersed system.

The classification of surfactants is very diverse and in some cases contradictory. Several attempts have been made to classify according to different criteria. According to Rebinder, all surfactants according to their mechanism of action are divided into four groups:

– wetting agents, defoamers and foam formers, i.e. active at the liquid-gas interface. They can reduce the surface tension of water from 0.07 to 0.03–0.05 J/m2;

– dispersants, peptizers;

– stabilizers, adsorption plasticizers and thinners (viscosity reducers);

– detergents with all the properties of surfactants.

The classification of surfactants by functional purpose is widely used abroad: thinners, wetting agents, dispersants, deflocculants, foaming agents and defoamers, emulsifiers, disperse system stabilizers. Binders, plasticizers and lubricants are also distinguished.

Based on their chemical structure, surfactants are classified depending on the nature of hydrophilic groups and hydrophobic radicals. Radicals are divided into two groups - ionic and nonionic, the former can be anionic and cationic.

Nonionic surfactants contain non-ionizing final groups with high affinity for the dispersion medium (water), which usually include atoms of oxygen, nitrogen, and sulfur. Anionic surfactants are compounds in which a long hydrocarbon chain of molecules with low affinity for the dispersion medium is part of the anion formed in an aqueous solution. For example, COOH is a carboxyl group, SO 3 H is a sulfo group, OSO 3 H is an ether group, H 2 SO 4, etc. Anionic surfactants include salts of carboxylic acids, alkyl sulfates, alkyl sulfonates, etc. Cationic substances form cations containing a long hydrocarbon radical in aqueous solutions. For example, 1-, 2-, 3- and 4-substituted ammonium, etc. Examples of such substances can be amine salts, ammonium bases, etc. Sometimes a third group of surfactants is isolated, which includes amphoteric electrolytes and ampholytic substances, which, depending on By nature, the dispersed phase can exhibit both acidic and basic properties. Ampholytes are insoluble in water, but are active in non-aqueous media, such as oleic acid in hydrocarbons.

Japanese researchers propose a classification of surfactants according to physicochemical properties: molecular weight, molecular structure, chemical activity, etc. The gel-like shells on solid particles resulting from surfactants as a result of different orientations of polar and non-polar groups can cause various effects: liquefaction; stabilization; dispersing; defoaming; binding, plasticizing and lubricating actions.

The surfactant has a positive effect only at a certain concentration. There are very different opinions on the issue of the optimal amount of administered surfactants. P. A. Rebinder points out that for particles

1–10 µm the required amount of surfactant should be 0.1–0.5%. Other sources give values ​​of 0.05–1% or more for different dispersion. For ferrites, it was found that in order to form a monomolecular layer during dry grinding, surfactants must be taken at the rate of 0.25 mg per 1 m 2 of the specific surface of the initial product; for wet grinding – 0.15–0.20 mg/m2. Practice shows that the surfactant concentration in each specific case must be selected experimentally.

In the technology of ceramic SEMs, four areas of application of surfactants can be distinguished, which make it possible to intensify physicochemical changes and transformations in materials and control them during the synthesis process:

– intensification of the processes of fine grinding of powders to increase the dispersion of the material and reduce the grinding time when achieving a given dispersion;

– regulation of the properties of physical and chemical disperse systems (suspensions, slips, pastes) in technological processes. What is important here are the processes of liquefaction (or a decrease in viscosity with an increase in fluidity without a decrease in moisture content), stabilization of rheological characteristics, defoaming in disperse systems, etc.;

– control of torch formation processes when spraying suspensions when obtaining the specified size, shape and dispersion of the spray torch;

– increasing the plasticity of molding compounds, especially those obtained when exposed to elevated temperatures, and the density of manufactured blanks as a result of the introduction of a complex of binders, plasticizers and lubricants.

Before the invention of soap, fat and dirt were removed from the skin using ash and fine river sand. The Egyptians washed their faces with a paste based on beeswax mixed with water. IN Ancient Rome When washing, they used finely ground chalk, pumice, and ash. Apparently, the Romans were not bothered by the fact that during such ablutions, along with the dirt, it was possible to “scrape off” part of the skin itself. The credit for the invention of soap probably belongs to the Gallic tribes. According to Pliny the Elder, the Gauls made an ointment from the tallow and ash of the beech tree, which was used to dye hair and treat skin diseases. And in II century, it began to be used as a detergent.

The Christian religion considered washing the body a “sinful” act. Many "saints" were known only for not washing their entire lives. But people have long noticed the harm and health hazards of skin pollution. Already in the 18th century, soap making was established in Rus', and in a number of European countries even earlier.

The technology for making soap from animal fats has evolved over many centuries. First, a fat mixture is prepared, which is melted and saponified - boiled with alkali. To hydrolyze fat in an alkaline environment, take a little melted lard, about 10 ml of ethyl alcohol and 10 ml of alkali solution. Table salt is also added here and the resulting mixture is heated. This produces soap and glycerin. Salt is added to precipitate glycerin and impurities. Two layers are formed in the soap mass - the core (pure soap) and the soapy lye .

Soap is also produced industrially.

Saponification of fats can also occur in the presence of sulfuric acid (acid saponification). This produces glycerol and higher carboxylic acids. The latter are converted into soaps by the action of alkali or soda. The starting materials for soap production are vegetable oils (sunflower, cottonseed, etc.), animal fats, as well as sodium hydroxide or soda ash. Vegetable oils They are preliminarily hydrogenated, i.e. they are converted into solid fats. Fat substitutes are also used - synthetic carboxylic fatty acids with a large molecular weight. Soap production requires large quantities of raw materials, so the task is to obtain soap from food products. The carboxylic acids necessary for soap production are obtained by oxidation of paraffin. By neutralizing acids containing from 9 to 15 carbon atoms per molecule, toilet soap is obtained, and from acids containing from 16 to 20 carbon atoms, laundry soap and soap for technical purposes are obtained.

Soap composition

Conventional soaps consist primarily of a mixture of salts of palmitic, stearic and oleic acids. Sodium salts form solid soaps, potassium salts form liquid soaps.

Soap - sodium or potassium salts of higher carboxylic acids,
obtained as a result of hydrolysis of fats in an alkaline environment

The structure of soap can be described by the general formula:

R – COOM

where R is a hydrocarbon radical, M is a metal.

Benefits of soap:

a) simplicity and ease of use;

B) removes sebum well

B) has antiseptic properties

Disadvantages of soap and their elimination:

Soap structure- sodium stearate.

The sodium stearate molecule has a long non-polar hydrocarbon radical (indicated by a wavy line) and a small polar part:

The surfactant molecules on the boundary surface are arranged in such a way that the hydrophilic groups of carboxyl anions are directed into the water, and the hydrophobic hydrocarbon groups are pushed out of it. As a result, the surface of the water is covered with a palisade of surfactant molecules. Such water surface has lower surface tension, which promotes rapid and complete wetting of contaminated surfaces. By reducing the tension surface of water, we increase its wetting ability.

You can buy surfactants (surfactants)we have. Call: (+38 044) 228-08-72.

Surfactants (surfactants)- chemical compounds that, concentrating at the interface, cause a decrease in surface tension.

Due to their washing, wetting, emulsifying, dispersing and other valuable properties, surfactants are widely used in the production of detergents and cleaning products, cosmetics and pharmaceuticals. Latex. Rubber. Polymers. Chemical plant protection products, textiles, leather and paper, building materials, corrosion inhibitors, during oil production, transportation and refining, etc. Most surfactants (estimated at 55-60%) are used for the production of synthetic detergents (SDCs).

Currently used synthetic surfactants (surfactants) are divided into 4 classes:

• anionic surfactants - compounds that dissociate in aqueous solutions to form anions that cause surface activity. Among them highest value have linear alkyl benzene sulfonate, sulfates and sulfoesters of fatty acids;
• amphoteric (ampholytic) surfactants - compounds that ionize in aqueous solutions and behave depending on conditions (mainly on the pH environment), i.e., in an acidic solution they exhibit the properties of cationic surfactants, and in an alkaline solution - anionic surfactants. Among the main amphoteric surfactants, alkyl betaines, alkylaminocarboxylic acids, alkyl imidazoline derivatives, and alkylaminoalkanesulfonates should be noted.
• nonionic surfactants - compounds that dissolve in water without ionizing. The solubility of nonionic surfactants in water is determined by the presence of functional groups in them. As a rule, they form nitrates in an aqueous solution due to the formation of hydrogen bonds between water molecules and the oxygen atoms of the polyethylene glycol part of the surfactant molecule. These include: polyglycol ethers of fatty alcohols and acids, polyglycol esters of fatty acid amides, acylated or alkylated polyglycol ethers of alkylamides.
• cationic surfactants - compounds that dissociate in an aqueous solution to form cations that determine surface activity. Among cationic surfactants, quaternary ammonium compounds, imidazalines, and fatty amines are of greatest importance.

The main raw materials for large-scale production of surfactants are products of oil refining and petrochemical synthesis: low molecular weight and higher paraffins, olefins, synthetic fatty acids, higher fatty alcohols, alkyl derivatives of benzene and phenol, ethylene oxide, etc.

It is a known fact that the first surfactant - soap - has been “living” for almost 4000 years, but in the 50s it gave way to detergents and cleaners based on alkylbenzenesulfonate. However, 9 million tons of soap are consumed annually in the world. Thus, soap remains the most common surfactant in the world, followed by ABS. Soap, according to strategic marketing estimates, has been in the so-called “saturation phase” for many years. The “phase of degeneration” will certainly never occur as long as humanity lives.

Surfactants in cosmetics

The concept of “Cosmetics” unites a wide range of different products intended for the care of human hair and body. This is hair shampoo and liquid soap; hair dyes; hair care products after washing; rinses, balms, etc.; cosmetic creams for the face, body, hands, including therapeutic and prophylactic effects.

Modern shampoos are multifunctional products that contain various ingredients that provide softness, stability, foaming, and improve appearance and the neck of the hair.
The basis of the raw components of shampoos are surfactants, as well as various useful additives, including biologically active ones.
Anionic substances are used as the main surfactants, which provide a sufficient cleaning effect and foaming while being gentle on the skin and hair.

For conventional commercial shampoos, anionic surfactants (alkyl sulfates and alkyl ether sulfates)
In order to obtain “soft” shampoos, alkyl amidoether sulfates, sulfosuccinates, and, to a lesser extent, isothionates, sarcosinates, etc. are used in mixtures with them.
Auxiliary surfactants include amphoteric, nonionic and cationic substances. They are necessary in shampoo formulations to increase the compatibility of main surfactants with skin and hair, increase foaming properties, regulate viscosity, and reduce the degreasing effect. For this purpose, imidazoline derivatives, betaines, alkylamides, and amine oxides are widely used.
Alkylolamides and glycol ethers of fatty alcohols are used as solubilizers for the introduction of fragrances and other hydrophobic components (oils, biologically active substances).

Cationic, non-ionic surfactants, beta-ins are used as conditioning agents that remove charges of static electricity and make it easier to comb dry and wet hair.

The most effective antistatic agents are cationic surfactants - quaternary ammonium compounds, although there are problems of incompatibility with anionic surfactants. However, in a mixture with nonionic and amphoteric substances, it is possible to achieve the desired effect and maintain the stability of the finished product.
Amine oxides and oxyesters of alkyl phosphates are also used to soften hair and reduce its electrification.

A separate group among shampoos, liquid soap, bath foams are made up of especially “soft” compositions intended for children and adults with sensitive skin, i.e. compositions of increased softness in terms of impact on the skin. Here the requirements for raw materials are especially high. Most often, a mixture of alkyl ether sulfates with amphoteric surfactants - imidazoline derivatives, as well as betaines and monoalkyl sulfosuccinates is used as the active principle. The same base is used in anti-dandruff and medicinal shampoos.

Anionic surfactants

The main types of surfactants used in SMS are alkylbenzenesulfonates with a linear alkyl chain (LABS) and derivatives of C12-C15 alcohols (ethoxylates, sulfates, ethoxysulfates of alcohols). LABS and alcohol sulfates, along with soap, are classified as anionic surfactants, while alcohol ethoxylates are classified as non-ionic (non-ionic) surfactants.

Nonionic surfactants

The second important type of surfactant for SMS are nonionic surfactants obtained by oxyethylation of higher fatty alcohols or alkylphenols

The most commonly used nonionic surfactants are fatty alcohol oxyethylates, which can be based on either linear or branched alcohols. If ethoxylates based on long-chain alcohols (C12-C15), due to their better cleaning ability, are more often used in CMC formulations for laundries, then for cleaning hard surfaces it is preferable to use ethoxylates based on short-chain alcohols (C9-C11). These ethoxylates are characterized by better wetting ability and contact angle with respect to solid surfaces. In general, nonionic surfactants, due to the variability of their base and the degree of oxyethylation or propoxylation, can in an ideal way tailored to a specific task. They, as a rule, are superior to anionic surfactants in both cleaning and degreasing effects and, depending on the profile of use, emulsify more or less oils and fats.

Amphoteric surfactants

From the group of amphoteric surfactants, betaine derivatives (for example, cocaminopropyl betaine) are most often used. In combination with anionic surfactants, they improve foaming ability and increase the safety of formulations, and when combined with cationic polymers, they enhance the positive effects of silicones and polymers on hair and skin. These derivatives are obtained from natural raw materials, so they are quite expensive components.

We offer such surfactants (surfactants):