Inorganic fibers, their types, structure, properties. Fibers of the past, present and future. Choosing a path is not an easy task. What is knitted from inorganic fibers

The 19th century was marked by important discoveries in science and technology. A sharp technical boom affected almost all spheres of production, many processes were automated and moved to a qualitatively new level. The technical revolution did not bypass the textile industry either - in 1890 in France, for the first time, a fiber made using chemical reactions was obtained. The history of chemical fibers began with this event.

Types, classification and properties of chemical fibers

According to the classification, all fibers are divided into two main groups: organic and inorganic. Organic fibers include artificial and synthetic fibers. The difference between them is that artificial ones are created from natural materials (polymers), but using chemical reactions. Synthetic fibers use synthetic polymers as raw materials, while the processes for obtaining fabrics do not fundamentally differ. Inorganic fibers include a group of mineral fibers that are obtained from inorganic raw materials.

Hydrate cellulose, cellulose acetate and protein polymers are used as raw materials for artificial fibers, for synthetic ones - carbo-chain and hetero-chain polymers.

Due to the fact that chemical processes are used in the production of chemical fibers, the properties of fibers, primarily mechanical, can be changed by using different parameters of the production process.

The main distinguishing properties of chemical fibers in comparison with natural ones are:

• high strength;
• the ability to stretch;
• tensile strength and long-term loads of different strength;
• resistance to light, moisture, bacteria;
• crease resistance.

Some special types are resistant to high temperatures and aggressive environments.

GOST chemical threads

According to the All-Russian GOST, the classification of chemical fibers is rather complicated.

Artificial fibers and threads, according to GOST, are divided into:

• artificial fibers;
• artificial threads for cord fabric;
• artificial threads for technical products;
• technical threads for twine;
• artificial textile threads.

Synthetic fibers and threads, in turn, consist of the following groups: synthetic fibers, synthetic threads for cord fabric, for technical products, film and textile synthetic threads.

Each group includes one or more subspecies. Each subspecies has its own code in the catalog.

Technology of obtaining, production of chemical fibers

The production of man-made fibers has great advantages over natural fibers:

• firstly, their production does not depend on the season;
• secondly, the production process itself, although quite complex, is much less laborious;
• thirdly, it is possible to obtain fiber with preset parameters.

From a technological point of view, these processes are complex and always consist of several stages. First, the starting material is obtained, then it is converted into a special spinning solution, then the fibers are formed and finished.

Various techniques are used to form fibers:

• using a wet, dry or dry-wet solution;
• the use of cutting with metal foil;
• drawing from the melt or dispersion;
• drawing;
• flattening;
• gel molding.

Application of chemical fibers

Man-made fibers are widely used in many industries. Their main advantage is their relatively low cost and long service life. Fabrics made of chemical fibers are actively used for sewing special clothing, in the automotive industry - for strengthening tires. In technology of various kinds, non-woven materials made of synthetic or mineral fibers are often used.

Textile chemical fibers

As a raw material for the production of textile fibers of chemical origin (in particular, for the production of synthetic fibers), gaseous products of oil and coal processing are used. Thus, fibers are synthesized, which differ in composition, properties and combustion method.

Among the most popular:

• polyester fibers (lavsan, crimplen);
• polyamide fibers (nylon, nylon);
• polyacrylonitrile fibers (nitron, acrylic);
• elastane fiber (lycra, dorlastan).

Among artificial fibers, the most common are viscose and acetate. Viscose fibers are obtained from cellulose - mainly spruce. Through chemical processes, this fiber can be given a visual resemblance to natural silk, wool or cotton. Acetate fiber is made from cotton waste, so it absorbs moisture well.

Chemical fiber nonwovens

Nonwovens can be made from both natural and man-made fibers. Often nonwovens are made from recyclable materials and waste from other industries.

The fibrous base, prepared by mechanical, aerodynamic, hydraulic, electrostatic or fiberising methods, is bonded.

The main stage in the production of nonwoven materials is the stage of bonding the fibrous base, obtained in one of the following ways:

1. Chemical or adhesive (adhesive)- the formed web is impregnated, coated or sprayed with a binder in the form of an aqueous solution, the application of which can be continuous or fragmented.
2. Thermal- this method uses the thermoplastic properties of some synthetic fibers. Sometimes the fibers that make up the nonwoven fabric are used, but in most cases, a small amount of low melting point fibers (bicomponent) is deliberately added to the nonwoven fabric at the spinning stage.

Chemical fiber industry facilities

Since chemical production covers several areas of industry, all chemical industry objects are divided into 5 classes depending on raw materials and field of application:

• organic matter;
• inorganic substances;
• organic synthesis materials;
• pure substances and chemicals;
• pharmaceutical and medical group.

According to the type of purpose, the objects of the chemical fiber industry are divided into main, general plant and auxiliary.

For the manufacture of textile materials, a wide variety of fibers are used, which it is advisable to classify taking into account their origin, chemical composition and other characteristics.

Depending on the origin, textile fibers are divided into natural and chemical. Chemical, in turn, are subdivided into artificial and synthetic. Artificial fibers are made from natural fiber-forming polymers such as cellulose. These include viscose, copper-ammonia, acetate, protein fibers. Synthetic fibers are produced by synthesis from low molecular weight compounds. The raw materials, as a rule, are the products of oil refining and coal. Synthetic fibers include polyamide, polyester, polyacrylonitrile, polyurethane, polyvinyl alcohol, etc. Synthetic fibers are widespread, their balance in the total production of textile fibers is increasing. The classification of textile organic fibers is shown in Fig. 3.

Synthetic fibers and threads are also subdivided into heterochain and carbon chain. Fibers and threads are called carbon chain fibers and threads that are obtained from polymers having only carbon atoms in the main chain of macromolecules (polyacrylonitrile, polyvinyl chloride, polyvinyl alcohol, polyolefin, carbon).

Rice. 3. Classification of organic textile fibers

Heterochain fibers are formed from polymers, the main molecular chain of which, in addition to carbon atoms, contains atoms of other elements - O, N, S (polyamide, polyester, polyurethane).

Artificial fibers are mostly cellulose processing products (viscose, polynose, copper-ammonia - cellulose hydrate; acetate, diacetane - cellulose acetate). In a small volume, artificial protein fibers (zein, casein, collagen) are produced from fibrillar proteins of milk, skin, and plants.

In the above classification (see Fig. 3), fibers and threads are classified as organic. In most cases, they are used for the production of textile materials for household use. In organic fibers, the main chain macromolecules contain atoms of carbon, oxygen, sulfur, nitrogen. In addition to organic fibers, there are inorganic fibers, the main chain macromolecules of which contain inorganic atoms (magnesium, aluminum, copper, silver, etc.). Natural inorganic fibers include asbestos fibers, inorganic chemical fibers - glass fibers and metal made of steel, copper, bronze, aluminum, nickel, gold, silver in various ways (alunite, lurex).

In addition to those already listed, there are fibers made from natural inorganic compounds. They are divided into natural and chemical.

Natural inorganic fibers include asbestos, a fine-fibrous silicate mineral. Asbestos fibers are fire-resistant (the melting temperature of asbestos reaches 1500 ° C), alkali- and acid-resistant, non-thermal conductivity.

Elementary asbestos fibers are combined into technical fibers, which serve as the basis for threads used for technical purposes and in the manufacture of fabrics for special clothing that can withstand high temperatures and open fire.

Chemical inorganic fibers are subdivided into glass fibers (silicon) and metal-containing ones.

Silicon fibers, or glass fibers, are made from molten glass in the form of elementary fibers with a diameter of 3-100 microns and a very long length. In addition to them, staple fiberglass is made with a diameter of 0.1-20 microns and a length of 10-500 mm. Fiberglass is non-combustible, chemically resistant, has electrical, heat and sound insulation properties. It is used for the manufacture of ribbons, fabrics, nets, nonwoven fabrics, fibrous webs, cotton wool for technical needs in various sectors of the country's economy.

Artificial metal fibers are produced in the form of filaments by gradually drawing (drawing) a metal wire. This is how copper, steel, silver, gold threads are obtained. Aluminum filaments are made by cutting flat aluminum tape (foil) into thin strips. Metallic threads can be given different colors by applying colored varnishes to them. To give greater strength to metal threads, they are wrapped with threads of silk or cotton. When the threads are covered with a thin protective synthetic film, transparent or colored, combined metal threads are obtained - metlon, lurex, alunite.

The following types of metal threads are produced: rounded metal thread; flat thread in the form of a ribbon - flattened; twisted thread - tinsel; flat rolled with silk or cotton thread - strand.

In addition to metal, metallized threads are made, which are narrow ribbons of films with a metal coating. Unlike metal threads, metallized threads are more elastic and fusible.

Metallic and metallized threads are used for the production of fabrics and knitwear for evening dresses, gold embroidery, as well as for decorative finishing of fabrics, knitwear and piece goods.

End of work -

This topic belongs to the section:

General information about fibers. Fiber classification. Basic properties of fibers and their dimensional characteristics

In the production of garments, the most diverse materials are used, these are fabrics, knitwear, natural and artificial nonwovens .. knowledge of the structure of these materials, the ability to determine their properties to understand .. the largest volume in the garment industry is made up of products made of textile materials ..

If you need additional material on this topic, or you did not find what you were looking for, we recommend using the search in our base of works:

What will we do with the received material:

If this material turned out to be useful for you, you can save it to your page on social networks:

All topics in this section:

Lecture 1
Introduction. Fibrous materials 1. Goals and objectives of the course "Materials science of garment production". 2. General information about

Cotton fiber
Cotton refers to the fibers that cover the seeds of the annual cotton plant. Cotton is a thermophilic plant that consumes a lot of moisture. Grows in hot areas. Izv

Natural fibers of animal origin
The main substance that makes up natural fibers of animal origin (wool and silk) are naturally synthesized animal proteins - keratin and fibroin. Difference in molecular structure

Natural silk
Natural silk is the name given to thin continuous threads secreted by the glands of silkworm caterpillars during cocoon curling before pupation. The main industrial value is the silk of the domesticated mulberry

B. Chemical fibers
The idea of ​​creating chemical fibers was embodied at the end of the 19th century. thanks to the development of chemistry. The prototype of the process of obtaining chemical fibers was the formation of a silkworm thread

Artificial fibers
Artificial fibers include fibers from cellulose and its derivatives. These are viscose, triacetate, acetate fibers and their modifications. Viscose fiber is made from cellulose

Synthetic fibers
Polyamide fibers. The most widely used nylon fiber is obtained from the products of processing coal and oil. Under the microscope, polyamide fibers are

Types of textile threads
The basic element of a fabric or knitted fabric is a thread. By structure, textile threads are divided into yarns, multifilaments and monofilaments. These threads are called primary

Basic spinning processes
The fibrous mass of natural fibers, after collection and primary processing, goes to the spinning mill. Here, from relatively short fibers, a continuous strong thread is produced - yarn. This n

Weaving production
A textile is a textile fabric formed by interweaving two mutually perpendicular yarn systems on a weaving machine. The fabric formation process is called weaving.

Fabric finishing
Fabrics taken off the loom are called harsh fabrics or harsh fabrics. They contain various impurities and impurities, have an ugly appearance and are unsuitable for making garments.

Cotton fabrics
During cleaning and preparation, cotton fabrics undergo acceptance and grading, singeing, desizing, bleaching (bleaching), mercerization, and naping. Cleaning and software

Linen fabrics
Cleaning and preparation of linen fabrics is usually carried out in the same way as in cotton production, but more carefully, repeating the operations several times. This is due to the fact that linseed

Woolen fabrics
Woolen fabrics are divided into combed (stone) and woolen fabrics. They differ from each other in appearance. Combed fabrics are thin, with a clear weaving pattern. Cloth - more thick

Natural silk
Cleaning and preparation of natural silk is carried out in the following order: acceptance and sorting, singeing, boiling, bleaching, revitalization of bleached fabrics. When at

Man-made fabrics
Fabrics made of artificial and synthetic fibers do not have natural impurities. They can contain mainly easily washable substances, such as dressing, soap, mineral oil, etc.

Fibrous composition of fabrics
For the manufacture of clothing, fabrics made from natural (wool, silk, cotton, linen), artificial (viscose, polynose, acetate, copper-ammonia, etc.), synthetic (lava

Methods for determining the fibrous composition of tissues
Organoleptic is a method in which the fibrous composition of tissues is established using the senses - vision, smell, touch. Evaluate the appearance of the fabric, its ink, wrinkle resistance

Weave fabrics
The location of the warp and weft threads relative to each other, their relationship determines the structure of the fabric. It should be emphasized that the structure of fabrics is influenced by: the type and structure of the warp and weft threads.

Fabric finishing
The finish that gives the fabrics a presentation affects its properties such as thickness, stiffness, drape, wrinkle, air permeability, water resistance, gloss, shrinkage, fire resistance

Density of fabric
Density is an essential indicator of tissue structure. Weight, durability, air permeability, heat-shielding properties, rigidity, drape of fabrics depend on density. Each of

Phases of tissue structure
When weaving, the warp and weft threads mutually bend each other, as a result of which they are arranged in a wave-like manner. the degree of bending of the warp and weft yarns depends on their thickness and stiffness, type of

Fabric surface structure
Depending on the structure of the front side, fabrics are divided into smooth, pile, fleecy and felted. Smooth fabrics are those that have a clear weave pattern (calico, chintz, satin). In the process of

Fabric properties
Layout: Geometric properties Mechanical properties Physical properties Technological properties Fabrics made from threads and yarns are different

Geometric properties
These include the length of the fabric, its width, thickness and weight. The length of the fabric is determined by measuring it in the direction of the warp threads. When laying the fabric before cutting, the length of the piece

Mechanical properties
During the operation of clothing, as well as during processing, fabrics are subjected to various mechanical influences. Under these influences, tissues stretch, bend, and experience friction.

Physical properties
The physical properties of fabrics are divided into hygienic, heat-shielding, optical and electrical. Hygienic is considered to be the properties of tissues that significantly affect the com

Wear resistance of fabric
The durability of fabrics is characterized by their ability to withstand destructive factors. In the process of using garments, they are affected by light, sun, moisture, stretching, compression, torsion

Technological properties of fabrics
During the production process and during the operation of clothing, such properties of fabrics appear that must be taken into account when designing clothing. These properties significantly affect the technological

Gasket materials
5. Adhesive materials. 1. ASSORTMENT OF FABRICS According to the type of raw materials, the entire assortment of fabrics is divided into cotton, linen, woolen and silk. Silk includes

Adhesive materials
Semi-rigid interlining fabric with a dotted polyethylene coating is a cotton fabric (coarse calico or madapolam), coated on one side with polyethylene powder under high pressure

The choice of materials for a garment
In the production of garments, a variety of materials are used: fabrics, knitted and non-woven fabrics, duplicated, film materials, natural and artificial fur, natural and artificial

Product quality
In the manufacture of clothing and other garments, fabrics, knitted and non-woven fabrics, film materials, artificial leather and fur are used. The whole set of these materials is called assortment

Quality materials for clothing
high quality materials must be used to make good clothes. What is quality? The quality of a product is understood as a combination of properties that characterize the degree of suitability

Grade of materials
All materials at the final stage of production are subject to control. At the same time, the level of quality of the material is assessed and the grade of each piece is established. A grade is a gradation of product quality.

Grade of fabrics
Determination of the grade of fabrics is of great importance. The type of fabric is determined by an integrated method for assessing the level of quality. At the same time, deviations of indicators of physical and mechanical properties from the norms,

Defects in the appearance of tissues
defect Type of defect Description Production stage at which the defect occurs Saso

These are fibers obtained from organic natural and synthetic polymers. Depending on the type of raw material, chemical fibers are subdivided into synthetic (from synthetic polymers) and artificial (from natural polymers). Sometimes fibers obtained from inorganic compounds (glass, metal, basalt, quartz) are also referred to as chemical fibers. Chemical fibers are produced in industry in the form of:

1) monofilaments (single fiber of long length);

2) staple fiber (short lengths of fine fibers);

3) filament yarns (a bundle consisting of a large number of thin and very long fibers, connected by twisting), filament yarns, depending on the purpose, are divided into textile and technical, or cord yarns (thicker yarns of increased strength and twist).

Man-made fibers - fibers (threads) obtained by industrial methods in a factory.

Chemical fibers, depending on the feedstock, are divided into main groups:

artificial fibers are obtained from natural organic polymers (for example, cellulose, casein, proteins) by extracting polymers from natural substances and chemical action on them

synthetic fibers are produced from synthetic organic polymers obtained by synthesis reactions (polymerization and polycondensation) from low-molecular compounds (monomers), the feedstock for which are products of oil and coal processing

mineral fibers - fibers obtained from inorganic compounds.

Historical reference.

The possibility of obtaining chemical fibers from various substances (glue, resins) was predicted as early as the 17th and 18th centuries, but it was not until 1853 that the Englishman Oudemars first proposed to form endless thin threads from a solution of nitrocellulose in a mixture of alcohol and ether, and in 1891 the French engineer I. de Chardonnay was the first to organize the production of such threads on an industrial scale. Since that time, the rapid development of the production of man-made fibers began. In 1896, the production of copper-ammonia fiber from cellulose solutions in a mixture of aqueous ammonia and copper hydroxide was mastered. In 1893, the Englishmen Cross, Bevan and Beadl proposed a method for producing viscose fibers from aqueous-alkaline solutions of cellulose xanthate, carried out on an industrial scale in 1905. In 1918-20, a method was developed for the production of acetate fiber from a solution of partially saponified cellulose acetate in acetone, and in 1935 production was organized protein fibers from milk casein.

In the photo on the right below - not chemical fiber, of course, but cotton fabric.

The production of synthetic fibers began with the release in 1932 of polyvinyl chloride fiber (Germany). In 1940, the most famous synthetic fiber, polyamide (USA), was produced on an industrial scale. Industrial production of polyester, polyacrylonitrile and polyolefin synthetic fibers took place in 1954-60. Properties. Chemical fibers often have high tensile strength [up to 1200 MN / m2 (120 kgf / mm2)], significant tensile elongation, good dimensional stability, crease resistance, high resistance to repeated and alternating loads, resistance to light, moisture, mold, bacteria, chemo heat resistance.

Physicomechanical and physicochemical properties of chemical fibers can be changed in the processes of forming, stretching, finishing and heat treatment, as well as by modifying both the feedstock (polymer) and the fiber itself. This makes it possible to create chemical fibers with a variety of textile and other properties even from one initial fiber-forming polymer (table). Chemical fibers can be used in mixtures with natural fibers in the manufacture of new assortments of textiles, significantly improving the quality and appearance of the latter. Production. For the production of chemical fibers from a large number of existing polymers, only those are used that consist of flexible and long macromolecules, linear or weakly branched, have a sufficiently high molecular weight and have the ability to melt without decomposition or dissolve in available solvents.

Such polymers are commonly referred to as fiber-forming polymers. The process consists of the following operations: 1) preparation of spinning solutions or melts; 2) fiber forming; 3) finishing of the spun fiber. The preparation of spinning solutions (melts) begins with the transfer of the initial polymer into a viscous state (solution or melt). Then the solution (melt) is cleaned from mechanical impurities and air bubbles and various additives are introduced into it for thermal or light stabilization of fibers, their matting, etc. The solution or melt prepared in this way is fed to the spinning machine to spin the fibers. Fiber spinning involves forcing a dope (melt) through the fine holes of the spinneret into an environment that solidifies the polymer into fine fibers.

Depending on the purpose and thickness of the fiber being formed, the number of holes in the die and their diameter can be different. When chemical fibers are spun from a polymer melt (for example, polyamide fibers), cold air serves as a medium that solidifies the polymer. If spinning is carried out from a solution of the polymer in a volatile solvent (for example, for acetate fibers), this medium is hot air in which the solvent evaporates (the so-called "dry" spinning process). When a fiber is spun from a polymer solution in a non-volatile solvent (for example, rayon fiber), the filaments solidify, falling after the spinneret into a special solution containing various reagents, the so-called precipitation bath ("wet" spinning method). The spinning speed depends on the thickness and purpose of the fibers, as well as on the spinning method.

When molded from a melt, the speed reaches 600-1200 m / min, from a solution by the "dry" method - 300-600 m / min, by the "wet" method - 30-130 m / min. Spinning solution (melt) in the process of converting streams of viscous liquid into thin fibers is simultaneously drawn (spinneret drawing). In some cases, the fiber is additionally stretched immediately after leaving the spinning machine (plasticizing drawing), which leads to an increase in the strength of V. x. and improving their textile properties. The finishing of chemical fibers consists in the processing of freshly formed fibers with various reagents. The nature of the finishing operations depends on the spinning conditions and the type of fiber.

At the same time, low molecular weight compounds (for example, from polyamide fibers), solvents (for example, from polyacrylonitrile fibers), acids, salts and other substances entrained by the fibers from the precipitation bath (for example, viscose fibers) are removed from the fibers. To impart such properties to the fibers as softness, increased slip, surface adhesion of single fibers, etc., after washing and cleaning, they are subjected to avivage treatment or oiling. The fibers are then dried on drying rollers, cylinders or drying chambers. After finishing and drying, some chemical fibers are subjected to additional heat treatment - heat setting (usually in a stretched state at 100-180 ° C), as a result of which the yarn shape is stabilized, as well as the subsequent shrinkage of both the fibers themselves and products made from them during dry and wet treatments at elevated temperatures.

Lit .:

Characterization of chemical fibers. Directory. M., 1966; Rogovin Z.A., Fundamentals of chemistry and technology for the production of chemical fibers. 3rd ed., Vol. 1-2, M.-L., 1964; Chemical fiber production technology. M., 1965. V.V. Yurkevich.

as well as other sources:

Great Soviet Encyclopedia;

Kalmykova E.A., Lobatskaya O.V. Materials science of sewing production: Textbook. Allowance, Minsk: Vysh. shk., 2001412s.

Maltseva E.P., Materials science of garment production, - 2nd ed., Revised. and additional Moscow: Light and food industry, 1983, 232.

Buzov B.A., Modestova T.A., Alymenkova N.D. Materials science of sewing production: Textbook. for universities, 4th ed., revised and enlarged., M., Legprombytizdat, 1986 - 424.

By chemical composition, fibers are subdivided on organic and inorganic fibers.

Organic fibers are formed from polymers containing carbon atoms directly connected to each other, or including, along with carbon, atoms of other elements.

Inorganic fibers are formed from inorganic compounds (compounds from chemical elements other than carbon compounds).

For the production of chemical fibers from a large number of existing polymers, only fiber-forming polymers are used. Fiber-forming polymers consist of flexible and long macromolecules, linear or weakly branched, have a sufficiently high molecular weight and have the ability to melt without decomposition or dissolve in available solvents.

Progress in the field of technology for the production of synthetic fibers with modified properties has reached such a level that it has become possible to obtain reinforcing materials that can compete with inorganic fibers.

Gypsum hard coatings. They are made of gypsum and diatomaceous earth with the addition of organic or inorganic fibers. Bulk density 850 kz / l, thermal conductivity coefficient 0.16 kcal i-hour-deg at 50 ° C, temporary compressive strength 10-40 kg / cm. They are used to protect insulation from mechanical damage and replace wet plaster.

Inorganic fibers - asbestos and fiberglass differ from organic fibers primarily by their higher operating temperature.

Inorganic fibers such as asbestos, glass and other minerals differ from organic ones primarily by their higher operating temperature.

One of the essential advantages of thermoplastics filled with inorganic fibers is their increased heat resistance as compared to unfilled ones. This is due to the significantly higher rigidity of the polymer, as a result of which its deformability decreases at elevated temperatures and the glass transition temperature rises somewhat. If the polymer well wets the filler and its effect extends over a significant volume, then the introduction of the filler causes a restriction of molecular mobility in the boundary layers, which

F 125 165 Inorganic fiber fabrics - glass, asbestos impregnated with organosilicon varnishes and epoxy resins

After a known modification, the methods of strength of materials are applicable to parts made of anisotropic materials. The list should start with wooden beams, moving on to all kinds of composites. The latter are a fairly plastic matrix reinforced with high-strength fibers. Matrices and fibers can be both organic and inorganic, including metals.

Fillers can be fibrous and powdery. The main purpose of fibrous fillers is to increase mechanical strength and reduce fragility. Compared to organic fibers, inorganic fibers increase the Martens heat resistance and heat resistance. Wood flour is often used as a filler - finely ground wood, but retaining its fibrous content. It is used in plastics of not very high quality, but it is the cheapest fibrous filler. A higher quality filler than wood flour is wood pulp and cotton wool, which is not suitable for textile production. Due to the cleaner and longer fiber, the fleece provides, with the same binder, greater mechanical strength for pressed products and better electrical parameters than wood flour and cellulose. Parts with high mechanical strength are obtained by using chopped fabric as filler. In this case, the press material is usually obtained in the form of textolite chips - finely chopped cotton fabric impregnated with appropriate polymers, usually phenol-formaldehyde.

Construction materials. Mainly metals and their alloys, as well as various inorganic and organic materials (polymers, plastics, fibers, ceramics, etc.) are used as material for machine-building structures. Recently, composite materials have found application, consisting of high-strength threads of glass, boron, carbon and a binder (polymers and metals). In building structures, concrete (a mixture of large and small stone particles bonded with cement), reinforced concrete (concrete reinforced with steel rods), brick, wood and other materials are used.

In most cases, plastics are made up of two main components, a binder and a filler. The binder is usually an organic polymer that deforms under pressure. Sometimes an inorganic binder is also used, for example, glass in micalex, cement in asbestos cement (6-1, 6-19). The filler, firmly adhering to the binder, can be powdery, fibrous, sheet (wood flour - fine sawdust, stone flour, cotton, asbestos or glass fiber, mica, paper, cloth), the filler significantly reduces the cost of plastic and at the same time can improve it mechanical characteristics (increase strength, reduce fragility). As a rule, the hygroscopicity and electrical insulating properties deteriorate as a result of the introduction of the filler; therefore, in plastics, from which high electrical insulating properties are required, the filler is most often absent.

Heat and sound insulation. Inorganic materials are used as heat and sound insulating materials: mineral wool, glass wool from continuous fiber, mineral wool slabs, glass staple fiber products, foam layers, foam glass blocks. For protection from sunlight, shields, blinds, curtains made of metallized fabric, and aluminum foil are used on the windows.

Inorganic composite materials based on silicon carbide fibers. Silicon carbide fibers are more effective for reinforcing ceramics than carbon fibers. Examples of such composite materials are discussed below.

Inorganic and polycrystalline fibers have low density, high strength and chemical resistance. Carbon, boric, glass and other fibers are widely used for the reinforcement of plastics and metals.

In addition to the binder, the composition of composite plastics includes the following components I) fillers of various origins to increase mechanical strength, heat resistance, reduce shrinkage and reduce the cost of the composition organic fillers - wood flour, cotton wool, cellulose, cotton cloth, paper, wood veneer, etc. inorganic - graphite, asbestos, quartz, fiberglass, fiberglass, carbon fibers, boron, etc. 2) plasticizers (dibutyl phthalate, castor oil, etc.) that increase ela-

Fiberglass, however, is not the only fiber in use today. Asbestos, a naturally occurring inorganic fiber, also has good strength, modulus of elasticity and other properties. Steel wire, drawn to a small diameter and properly heat-treated, can have a strength of about 420 kgf / mm and a modulus of elasticity 3 times higher than that of glass fibers. More exotic types of fibers are currently being intensively developed for aerospace technology, including fibers made from carbon and graphite, boron, beryllium and some carbides, but they are still too expensive for the construction industry. Even more exotic fibers are whiskers, the strength of which is close to theoretical. Some types of fibers and whiskers are presented in table. 1 .

In accordance with TU 193-54 MSPMHN, bose-fired heat-insulating products are made from a mixture of diatomite or tripoli, asbestos waste, organic or inorganic fiber and mineral binders in the form of plates, shells and segments and have the following characteristics

Products from silica fiberglass materials. For high-temperature-resistant thermal insulation, quartz, silica and kaolin inorganic fibers with a melting point of 1750-1800 ° C are used.

Common to them is the use of fibrous materials that provide high tensile strength, and binders such as organic resin, with which all the fibers are connected, which helps to evenly distribute the load over them. Glass of various types, organic and inorganic fibers or metals can be used as the main material. Binder materials can be polyester, silicophenol epoxy or chalk-12-

In addition, the compounds may contain active compounds. additives that reduce the viscosity of the compound, plasticizers, hardeners. initiators and inhibitors, the purpose of which is the same as in Varnishes. The composition of the compound can also include fillers - inorganic and organic powdered or fibrous materials used to reduce shrinkage, improve thermal conductivity, reduce the temperature coefficient of expansion and reduce cost. Powdered quartz, talc, mica dust, asbestos and glass fibers and a number of others are used as fillers.