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Surfactants (surfactants) — chemical compounds, which, concentrating on the interface, cause a decrease in the surface tension.

The first and most popular surfactant, which is many thousands of years old, is soap. And every year, despite the competition of new detergents and cleaning products, first based on alkylbenzenesulfonate, and now others, more than 9 million tons of soap are consumed in the world. It is soap that remains the most widespread surfactant in the world.

Due to the detergent, wetting, emulsifying, dispersing and other valuable properties of surfactants are widely used in the production of detergents and cleaning products, cosmetics and pharmaceuticals... And also for the production of latex, rubber, polymers, in the extraction, transportation and processing of oil, etc.

Pavs are chemical cleaners, detergents, as well as plant protection products, textiles, leather and paper, building materials, corrosion inhibitors. Most of the surfactants (about 60%) account for the production of detergents(SMS - synthetic detergents).

The main raw materials for the 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, etc.

Synthetic surfactants (surfactants) are divided into 4 classes:

• anionic surfactants - compounds that dissociate in aqueous solutions with the formation of anions that cause surface activity. Among them, the most important are alkylbenzenesulfonate, sulfates and sulfoesters of fatty acids;

• cationic surfactants - compounds that dissociate in an aqueous solution with the formation of cations that determine surface activity. Among cationic surfactants, the most important are quaternary ammonium compounds, imidazalines, and fatty amines.

• amphoteric (ampholytic) surfactants - compounds that in aqueous solutions, depending on the pH value of the medium, are differently ionized and act - in an acidic solution they exhibit the properties of cationic surfactants, and in an alkaline solution - anionic surfactants. The main amphoteric surfactants are alkyl betaines, alkylaminocarboxylic acids, derivatives of alkyl imidazolines, alkylaminoalkanesulfonates.
• nonionic surfactants - compounds that, in full accordance with the name, dissolve in water without ionizing. The solubility of nonionic surfactants in water is due to the presence of functional groups. As a rule, in an aqueous solution they form nitrates due to the occurrence of hydrogen bonds between water molecules and oxygen atoms of the polyethylene glycol part of the surfactant molecule. Nonionic surfactants include: polyglycol esters of fatty alcohols and acids, polyglycol esters of fatty acid amides, acylated or alkylated polyglycol esters of alkylamides.

Synthetic detergents

The main types of surfactants used in the composition of CMC 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, belong to anionic surfactant, ethoxylates of alcohols - to nonionic surfactants.
Second important species Surfactants for SMS are nonionic surfactants obtained by oxyethylation of higher fatty alcohols or alkyl phenols.
Non-ionic surfactants, as a rule, are superior to anionic surfactants in both cleaning and degreasing action and, depending on the profile of use, emulsify more or less oil and fat. Also, nonionic surfactants, due to the variability of their base and the degree of oxyethylation or propoxylation, can be ideally tailored to a specific task.
The most commonly used non-ionic surfactants are fatty alcohol oxyethylates. Ethoxylates based on long-chain alcohols (C12-C15), due to their better detergency, are more commonly used in CMC formulations for laundries, but for cleaning hard surfaces it is preferable to use ethoxylates based on short-chain alcohols (C9-C11). These ethoxy-lathes are distinguished by better wetting ability and wetting angle in relation to hard surfaces.

Cosmetics

Surfactants are widely used in cosmetics... - This is shampoo, liquid soap, rinses, hair dye and conditioners for the ear after washing. Pavas are also cosmetic creams for the face, body, hands, including therapeutic and prophylactic action.

Anionic substances (alkyl sulfates and alkyl ether sulfates) are used as the main surfactants, which provide a sufficient washing effect and foaming with a gentle action on the skin and hair.

Alkylolamides, glycol ethers of fatty alcohols are used as solubilizers for the introduction of perfumes and other hydrophobic components (oils, biologically active substances).

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

Amphoteric surfactants in combination with anionic surfactants, they improve the foaming ability and increase the harmlessness of formulations, and when combined with cationic polymers, they enhance the positive effect of silicones and polymers on hair and skin. These derivatives are obtained from natural raw materials; therefore, they are rather expensive components. Most commonly used derivatives of betaine (coaminopropyl betaine)

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 non-ionic and amphoteric substances, it is possible to achieve the desired effect and maintain the stability of the finished product.

Federal Agency for Science and Education

State educational institution

higher professional education

"Kazan State Technological University"

Nizhnekamsk Institute of Chemical Technology

Department of Chemistry

Specialty 240401

« Colloidal surfactants»

Completed by: Zaripova Z.I., 1806

Checked by: Nureeva E.N.

Nizhnekamsk 2011

Introduction …………………………………………………………………… 3

Classification of surfactants by polar groups ……………………………… .4

Anionic surfactants …………………………………………………………… .6

Nonionic surfactants …………………………………………………………… 13

Cationic surfactants ………………………………………………………… ... 18

Zwitter - ionic surfactants …………………………………………………… ... 22

Surfactant adsorption at interphase boundaries ………………………………… .25

Natural surfactants ……………………………………………………… ..26

Dermatological action of surfactants ………………………………………… 27

The impact of surfactants on the environment ………………………………… 30

Biodegradability ………………………………………………………… 31

Surfactant marking ………………………………………………………… 32

Environmental protection ……………………………………………… ... 33

Household use …………………………………………………… ..33

Bibliographic list ………………………………………………… 34

Introduction

Surfactants, substances that can accumulate (thicken) on the contact surface of two bodies, called the interface, or interface. At the interface of the surfactant. form a layer of increased concentration - an adsorption layer. Any substance in the form of a component of a liquid solution or gas (vapor), under appropriate conditions, can exhibit surface activity, that is, it can be adsorbed under the action of intermolecular forces on a particular surface, lowering its free energy. However, surfactants are usually called only those substances, the adsorption of which from solutions already at very low concentrations (tenths and hundredths of a%) leads to a sharp decrease in surface tension.

Typical surfactants - organic compounds diphilic structure, that is, containing atomic groups in the molecule that differ greatly in the intensity of interaction with the environment (in the most practically important case, water). So, surfactant molecules contain one or more hydrocarbon radicals that make up the oleo- or lipophilic part (it is also the hydrophobic part of the molecule), and one or more polar groups - the hydrophilic part. Oleophilic (hydrophobic) groups, weakly interacting with water, determine the tendency of the molecule to transition from an aqueous (polar) medium to a hydrocarbon (non-polar) one. Hydrophilic groups, on the contrary, keep the molecule in a polar medium or, if the surfactant molecule is in a hydrocarbon liquid, determine its tendency to transition to a polar medium. Thus, the surface activity of surfactants dissolved in non-polar liquids is due to hydrophilic groups, and those dissolved in water are due to hydrophobic radicals.

Classification of pavs by polar groups

The first surfactant classification is based on the charge of the polar group. It is generally accepted to subdivide surfactants into anionic, cationic, nonionic and zwitterionic. Surfactant molecules included in the latter group, under normal conditions, contain both charges: anionic and cationic. In the literature, they are often called "amphoteric" surfactants, but this term is not always correct and should not be used as a synonym for the term "zwitterionic" surfactant. Amphoteric surfactant is a substance that, depending on the pH of the solution, can be cationic, zwitterionic or anionic. A prime example of amphoteric organic matter serve as simple amino acids. Most of the so-called zwitterionic surfactants have similar properties. However, some zwitterionic surfactants retain one of the charges over a wide pH range, for example, compounds containing a cationic quaternary ammonium group. Thus, a surfactant containing carboxylate and quaternary ammonium groups will be zwitterionic down to very low pH values, but will not be amphoteric.

Most ionic surfactants are monovalent, but there are also important representatives of divalent anionic surfactants. The physical and chemical properties of ionic surfactants are influenced by the nature of the counterion. In most cases, sodium ion acts as a counter ion for anionic surfactants, while other cations, for example, lithium, potassium, calcium, or protonated amine ions, are used in this capacity only for special purposes. The counterions for cationic surfactants are usually halide ions or methyl sulfate ions.

Hydrophobic groups of surfactants are usually represented by hydrocarbon radicals, as well as polydimethylsiloxane or fluorocarbon groups. Surfactants of the last two types are especially effective in non-aqueous media.

For a small number of surfactants, there is some uncertainty in the classification. For example, surfactants containing amine oxides are sometimes referred to as zwitterionic, sometimes to cationic and even non-ionic surfactants. The charge of the molecules of these substances depends on the pH of the aqueous phase; we can assume that in the neutral state they carry anionic and cationic charges or are nonionic dipole molecules. Ethoxylated fatty amines containing an amino nitrogen atom and a polyoxyethylene chain can be included in the class of cationic or non-ionic surfactants. The non-ionic character of such surfactants predominates in the case of very long polyoxyethylene chains, while for short to medium lengths of polyoxyethylene chains physicochemical characteristics, as a rule, correspond to cationic surfactants. Surfactants containing an anionic group in the molecule, for example, sulfate, phosphate or carboxylate, and polyoxyethylene chains are also very common. Such surfactants, for example sulfoesters, etc., usually contain short polyoxyethylene chains, and therefore are always considered as anionic surfactants.

Hello dear visitor of our site!

In the language of chemists, surfactants (surfactants) are chemical compounds that can adsorb at the interface, one of which is usually water, and reduce surface tension…

All surfactants are divided into four main classes: anionic, cationic, nonionic, and ampholytic:

Anionic surfactants are compounds that dissociate in aqueous solutions to form anions (negatively charged ions), which cause surface activity. They have good sanitary and hygienic properties and are well combined with other surfactants.

Cationic surfactants are compounds that dissociate in an aqueous solution to form cations that determine surface activity; they have valuable properties - bactericidal.

Nonionic surfactants are compounds that dissolve in water without ionizing. Nonionic surfactants are less sensitive to salts that cause water hardness than anionic and cationic surfactants.

Ampholytic surfactants are widely used in the production of foaming detergents and shampoos, due to their mild effect on the skin. Depending on the pH value, they exhibit the properties of cationic or anionic surfactants.

Due to their detergent, 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, chemicals protection of plants, textiles, leather and paper, building materials, corrosion inhibitors, during the extraction, transportation and processing of oil, etc. Most of the surfactants are used for the production of synthetic detergents (CMC).

Today, everyone is shouting at the top of their voice about the dangers of surfactants, but no one really tells what exactly is harmful, and why ...

We will try to consider the surfactants used in the manufacture of washing powders. Their positive and negative sides.

In the production of washing powders, mainly anionic and nonionic surfactants are used. Nonionic surfactants, in comparison with anionic surfactants, have the ability to adsorb on tissues in smaller amounts. But again, one cannot say that anionic surfactants are worse than nonionic ones. There are a huge number of types of nonionic surfactants and anionic surfactants.

One of the main criteria environmental safety and the effect on the human body is the biodegradability of surfactants. Distinguish between primary and complete biodegradability. Primary means structural changes (transformation) of surfactants by microorganisms, leading to the loss of surface-active properties, and complete biodegradability means the final biodegradation of surfactants to carbon dioxide and water In simple language speaking: primary is when the surfactant is washed out completely during washing, and complete is when it completely decomposes when it enters the water space. The best surfactant - which has 100% primary and complete biodegradability. Biodegradability indicators of the main surfactant classes are given in the table:

Table 1. Indicators of biodegradation of the main classes of surfactants that are included in the composition of goods household chemicals:

Surfactant name	Primary biodegradation. OECD Screening Test (%)	Complete biodegradation
		closed bottle test (%)	modified screening test in (%)
Anionic surfactants
Linear alkylbenzenesulfonate	95	65	73
С14 – С18 a-Olefinsulfonates	99	85	85
С16 – С18 Sulfates of fatty alcohols	99	91	80
С12 – С15 Sulfates alcohol ethoxylates	99	86	-
С16 – С18 Methyl esters of sulfonated fatty acids	99	76	-
Nonionic surfactants
С16 – С18 Fatty alcohols 14 EO	99	86	80
С12 – С14 Fatty alcohols 30 EO	99	27	-
С12 – С14 Fatty alcohols 50 EO	98	-	-
С12 – С18 Fatty alcohols 6 EO 2 PO	98	83	68
С12 – С18 Fatty alcohols 5 EO 8 PO	70	15	-
С12 – С14 Fatty alcohols 10 PO	50-63	21	11
С13-С15 Oxo alcohols 7 EO	93	62	-
i-Nonylphenols 9 EO	6-78	5-10	8-17
n – С8 – С10 Alkylphenols 9 EO	84	29	-
С12 – С18 Amines 12 EO	88	33	-
EO / PO block polymers	32	0-10	18
Alkyl polyglycosides	-	71-73	72-80

As we can see, the table shows the main surfactants used in the production of detergents.

So it follows from the table that the primary biodegradability of anionic and nonionic surfactants is practically the same, and full depends on the surfactant formula. That is, when choosing a surfactant, in the production of household chemicals, you can choose how the best option anionic and nonionic surfactants, which will behave in the same way as part of SMS.

The formation of residual amounts of surfactants on the fabrics of linen and clothes is significantly influenced by the composition of the detergent composition, the concentration of the detergent solution, its initial temperature, the duration of contact of the fabric with the solution, and the amount of rinse water. Therefore, the introduction of nonionic surfactants into the composition reduces the degree of adsorption of anionic surfactants on tissues by 2–3 times. That is, we can safely say that the complex of surfactants (anionic and nonionic) is much more effective than the use of any one surfactant, both for washing and for safety.

Surfactants have relatively low toxicity to humans and animals. According to the degree of increase in toxicity, surfactants can be distributed in the following order: nonionic, anionic, cationic. When exposed to the skin and mucous membranes, synthetic surfactants can exhibit irritating and resorptive effects. It was found that compositions of anionic and nonionic compounds have less pronounced biological and toxic effects. Nonionic surfactants reduce adsorption anionic substances and only in large doses can they have a damaging effect on the skin. The greatest danger of surfactants and preparations based on them for people lies in their sensitizing effect, the ability to cause allergic reactions. Sensitization can occur with any route of entry of surfactants into the body.

As you can see, the use of anionic or nonionic surfactants alone does not guarantee product quality and safety. The best result is the use in the production of a complex of anionic and nonionic high-quality surfactants with the highest rate of biodegradability.

for several. orders of magnitude higher than in the volume of liquid, therefore, even with a negligible content in water (0.01-0.1% by weight), surfactants can reduce surface tension water at the border with air from 72.8 10 -3 to 25 · 10 -3 J / m 2, i.e. almost untilsurface tension hydrocarbon liquids. A similar phenomenon takes place at the border of the water surfactant solution- hydrocarbon liquid, which creates the prerequisites for the formation of emulsions.

The main quantitative characteristic of surfactants is the ability of a substance to reduce surface tension at the interface is the derivative of the surface tension with respect to the surfactant concentration as C tends to zero.

The volume of the surfactant liquid phase can contain
- or in the form of individual molecules (truly soluble surfactants),
-or unite in groups of several tens of molecules - The limiting concentration of surfactants in the solution, at which the formation of micelles begins, is called).

Surfactant structure

As a rule, surfactants are organic compounds with amphiphilic structure, that is, their molecules contain a polar part, a hydrophilic component (functional groups -OH, -COOH, -SOOOH, -O-, etc., or, more often, their salts -ONa, -COONa, -SOOONa and etc.) and non-polar (hydrocarbon) part, hydrophobic component. An example of a surfactant is ordinary soap (a mixture of sodium salts of fatty carboxylic acids - oleate, sodium stearate, etc.) and SMS(synthetic detergents) as well as alcohols, carboxylic acids, amines, etc.

Surfactant classification

• Ionic surfactants
  • Cationic surfactants
  • Anionic surfactants
  • Amphoteric

• Nonionic surfactants
  • Alkyl polyglucosides
  • Alkyl polyethoxylates

Anionic surfactants
- contain one or more polar groups in the molecule and dissociate in an aqueous solution with the formation of long-chain anions, which determine their surface activity. These are the groups: COOH (M), OSO 2 OH (M), SO 3 H (M), where M is metal (mono-, di- or trivalent). The hydrophobic part of the molecule is usually represented by saturated or unsaturated aliphatic chains or alkylaromatic radicals.

In anionic surfactants, the cation can be not only with a metal, but also with an organic base. This is often di- or triethanolamine. Surface activity begins to manifest itself at the length of the hydrocarbon hydrophobic chain C 8 and with increasing chain length increases up to total loss solubility of surfactants in water. Depending on the structure of the intermediate functional groups and the hydrophilicity of the polar part of the molecule, the length of the hydrocarbon part can reach C 18 .

Cationic surfactants
- dissociate in an aqueous solution to form a surface-active cation with a long hydrophobic chain and an anion (usually a halide, sometimes an anion of sulfuric or phosphoric acid).

Nitrogen-containing compounds predominate among cationic surfactants; also used substances that do not contain nitrogen: sulfonium compounds + X- and sulfoxonium + X-, phosphonium + X-, arsonium + X-, iodonium.

Cationic surfactants lower the surface tension less than anionic surfactants, but they chemically interact with the surface of the adsorbent, for example. with cellular proteins of bacteria, causing a bactericidal effect.

Ampholytic surfactants
- depending on the pH value, they exhibit the properties of cationic or anionic surfactants.

They contain in the molecule a hydrophilic radical and a hydrophobic moiety capable of being an acceptor or a proton donor, depending on the pH of the solution. Typically, these surfactants include one or more basic and acidic groups, and may also contain a nonionic polyglycolic group. At some pH values, called. isoelectric point, surfactants exist in the form of zwitterions. The ionization constants of acidic and basic groups of truly soluble amphoteric surfactants are very low, however, cation-oriented and anion-oriented zwitter ions are most often encountered. The cationic group is usually a primary, secondary or tertiary ammonium group, a pyridine or imidazoline residue. Instead of N m. atoms S, P, As, etc. Anionic groups are carboxyl, sulfonate, sulfoether or phosphate groups.

Nonionic PA
- high molecular weight compounds that do not form ions in an aqueous solution.

Their solubility is due to the presence in the molecules of hydrophilic ether and hydroxyl groups, most often a polyethylene glycol chain. When dissolved, hydrates are formed due to the formation of a hydrogen bond between the oxygen atoms of the polyethylene glycol residue and water molecules. Due to the rupture of the hydrogen bond with increasing temperature, the solubility of nonionic surfactants decreases, so for them the cloud point is the top. the temperature limit of micelle formation is an important indicator. Many compounds containing a mobile H atom (acids, alcohols, phenols, amines) react with ethylene oxide to form nonionic surfactants RO (C2H4O) nH. The polarity of one oxyethylene group is significantly less than the polarity of any acid group in anionic surfactants. Therefore, to give the molecule the required hydrophilicity and HLB value, depending on the hydrophobic radical, from 7 to 50 oxyethylene groups are required. A characteristic feature of nonionic surfactants is liquid state and low foaming in aqueous solutions.

Nonionic surfactants combine well with other surfactants and are often included in formulations

Due to their detergent, 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, plant protection chemicals, textiles, leather and paper, building materials, corrosion inhibitors, during the extraction, transportation and processing of oil, etc. Most of the surfactants are used for the production of synthetic detergents (CMC).

Surfactants have relatively low toxicity to humans and animals. According to the degree of increase in toxicity, surfactants can be distributed in the following order: nonionic, anionic, cationic. When exposed to the skin and mucous membranes, synthetic surfactants can exhibit irritating and resorptive effects. It was found that compositions of anionic and nonionic compounds have less pronounced biological and toxic effects. Nonionic surfactants reduce the adsorption of anionic substances and only in high doses can they have a damaging effect on the skin. The greatest danger of surfactants and preparations based on them for people lies in their sensitizing effect, the ability to cause allergic reactions. Sensitization can occur with any route of entry of surfactants into the body.

Sources of surfactant intake in aquatic environment

V water bodies Surfactants come in significant quantities with household (use of synthetic detergents in everyday life) and industrial wastewater (textile, oil, chemical industry, production of synthetic rubbers), as well as with runoff from agricultural land (included in insecticides, fungicides, herbicides and defoliants as emulsifiers).

The use of surfactants (surfactants)

Surfactants are widely used in industry, in agriculture, medicine and everyday life. The world production of surfactants is growing every year, and the share of nonionic substances... All types of surfactants are widely used in the preparation and use of synthetic polymers. The most important area of ​​consumption of micelle-forming surfactants is the production of polymers by emulsion polymerization. The type and concentration of the selected surfactants (emulsifiers) largely depend on the technological and physicochemical properties of the resulting latexes. Surfactants are also used in suspension polymerization. Usually used high-molecular surfactants - water-soluble polymers (volivinyl alcohol, cellulose derivatives, vegetable adhesives, etc.). By mixing varnishes or liquid oil-resin compositions with water in the presence of emulsifiers, emulsions are obtained that are used in the manufacture of plastics, leather substitutes, nonwovens, impregnated fabrics, water-borne paints, etc. High-molecular water-soluble surfactants, in addition to being used in the above technological. processes, used as flocculants in different types water treatment. With their help from Wastewater as well as from drinking water remove suspended impurities.

Information was borrowed from the following sources:

1) www.wikipedia.org

3) www.hydrodynamictechnology.com

Superficially active substances when using household chemicals, including washing powders, Special attention... This is due to many factors, such as biodegradation, toxic indicators, absorption capacity, and the main one is detergency. The essence of this indicator is how qualitatively Pav to wash fabrics from dirt.
This process can be described as follows: first, the PAV detergent solution wets the dirt on the fabric. As a result, a kind of penetrating layer of Pav appears around the pollution. Through microcracks, PAs penetrate into the places of contact between pollution and tissue, the contaminant is pulled out together with the carbon radical Pav into the dispersion medium, then the process of grinding mud particles, separation and stabilization in the washing solution takes place.
Now let's give a description of the main groups of Pav:
1. Anionic surfactants (APAS) organic compounds that, in the process of formation aqueous solution, form an anion with a long carbon radical carrier surface activity, while the cation is surface active. In other words, when an anionic surfactant gets into an aqueous medium, its molecule is divided into negatively charged particles of anions and positively charged cations. As a result, negative PAV anions are combined with positive dirt particles, transferring them into solution and thereby separating the dirt from the fabric.
Anionic Pav is used for softening, as detergents, foaming agents. Most effective in alkaline environments

These are the most common Pavs, which are almost 100% biodegradable.
2. Nonionic surfactants (nonionic surfactants), soluble in both acidic and alkaline media, do not dissociate in water. They have a high detergency.
They are effectively used in soft and hard waters and have a low foaming capacity. Biodegradable by an average of 85%. In washing powders, the percentage of input is very low, 1-2%.
3. Cationic surfactants (CSAS) are organic compounds that, dissociating in water, form a developed surface-active cation, while the anion is not active. These Pavs are used as a corrosion inhibitor, as a conditioning agent, as a disinfectant and as an antibacterial agent.
The adsorption layers of cationic PAs perform antistatic, conditioning functions and have a protective effect on the affected tissue fibers.
4. Amphoteric surfactants - compounds that contain both types of groups in the molecules: acid (most often carboxyl) and basic (usually amino group of different degrees of substitution). They can exhibit the properties of cationic, nonionic or anionic surfactants.
Ampholytic Pavs soften fabrics, have an antistatic effect, and are effective when used in hard and cold water... Ampholytic PAs are well combined with PAs of all types, have good foaming properties, bactericidal activity and dermatological properties.

From our point of view, it is necessary to pay attention to such a widespread Pav as fatty acid soap, it is found in almost all powders, many manufacturers base their strategy of promoting and promoting powders exclusively on the PR of this soap.

What you need to pay attention to, there are both pros and cons. The pluses include: naturalness, mild impact, etc.
The disadvantages include the following: firstly, soap, being a salt of a weak organic acid (more precisely, a salt formed by a mixture of three acids palmitic, margaric and stearic) and a strong base of sodium hydroxide, is hydrolyzed in water (that is, it is split by it) into acid and alkali. The acid reacts with hardness salts and forms new, already water-insoluble salts, which fall out in the form of a sticky white mass on clothes, hair, etc. This not very pleasant phenomenon is well known to everyone who tried to wash or wash in hard water ; secondly, the alkali hydrolysis product destroys and reduces the strength of the fibers that make up various fabrics. Polyamide fibers (nylon, nylon, perlon) are destroyed by soap especially intensively.

Information taken from the source