Production of modern chemical fibers briefly. Presentation on technology on the topic "Technology for the production of chemical fibers

Development of a technology lesson.

Developed by a technology teacher

"Secondary school No. 2 of the Akimat of Shakhtinsk"

Karaganda region of the Republic of Kazakhstan

Sultangareeva Louise Makhmutovna

Class 7

Chapter: Introduction to fabrics.

Duration: 1 hour

Topic: Chemical fibers, their properties. Technology for the production of chemical fibers.

Ecological influence of tissues on the human body.

create conditions for generalization, systematization and expansion of students' knowledge about textile fibers, their properties, fabric production processes;

contribute to the formation of knowledge about the technology of production of fabrics from chemical fibers and their range;

contribute to the identification of gaps in the knowledge of students and their correction;

to promote the development of the ability to analyze information, observation and attentiveness, thinking;

to promote the upbringing of positive motivation for the subject, activity in the work at the lesson, accuracy, as well as a culture of behavior.

• • Clarification and consolidation of knowledge about natural fibers.
  • Acquaintance with the technology of obtaining chemical fibers.
  • Non-woven materials from chemical fibers.
  • An assortment of fabrics.

Visibility and equipment:

Collections of samples of fabrics from chemical and natural fibers;

Power Point presentation "Production of fabrics from chemical fibers";

Information materials "Properties of fabrics made of chemical fibers"

DURING THE CLASSES.

Organizing time.

a) greeting;

b) identification of absent students;

c) organizing the attention of students.

Pay attention to the board on which fabric samples are placed (including non-woven ones - batting, synthetic winterizer).

Introductory part of the lesson.

1. The message of the topic of the lesson. Introduction to the topic of the lesson.

Look at your clothes. What is it made of?

Do you know what materials these fabrics are made of?

Are these materials natural or man-made?

Take a look at the window curtains. What can you say about this fabric? What are its undoubted advantages? What about disadvantages?

Can this fabric be used to make clothes? Why?

Today in the lesson we will talk about chemical fibers, the technology of their production and the properties of fabrics made from these fibers.

2. Jointly with the students, the formulation of the learning objectives of the lesson:

What are we going to study today?

to study the features of the production of chemical fibers;

find out where it is advisable to use fabrics made of chemical fibers (in accordance with their properties).

3. Actualization of students' knowledge. Conversation.

What are the steps in fabric production?

Name the groups of fibers according to their origin.

4. Generalization of answers. Summing up the conversation.

III. Main part of the lesson

1. 1. Teacher's story "Production of chemical fibers" using Presentation materials.

Production technology chemical fibers of both groups is the same: raw materials (organic substances) + chemical solvents, a liquid viscous mass is obtained. This mass is forced through filters (dies), thereby forming threads. These filaments are then dipped into a bath of hardeners and, after processing and washing, are wound onto bobbins to form continuous filaments. The successes of modern chemistry make it possible to create chemical fibers both from natural materials, mainly cellulose obtained from wood, straw, and cotton waste. Such a fiber is called artificial, and from synthetic polymers, products of processing of coal, oil. This fiber is syntheticslogical(Entry in a notebook in the form of a diagram). It is very difficult to list the many chemical fibers that are used for the production of fabrics. And in laboratories, more and more of their types are synthesized.

1. Independent work of students

Problem. Research "Reasons and features of the creation of chemical fibers."

Work with Information material "Properties of fabrics from chemical fibers» by subgroups.

1. Presentation of the studied material. Carousel method. One of the team members goes to another team and tells the content of his material.
2. Discussion.

• • Reasons for creating chemical fibers (Cost. Dependence on natural and weather conditions. Other).
  • Stages of creation.
  • Properties of chemical fibers. (Special, original properties:

The strongest fiber;

Fiber with high hygienic properties;

Fabrics with high thread separation, etc.

1. Analysis of student responses. Addendum and clarification.
2. Working with a collection of tissue samples.

1. • name the numbers of samples of fabrics made from chemical fiber
   • determine the scope of this fabric in everyday life.

1. Student work in notebooks Recording the main steps of chemical fiber production»

IV. The final part of the lesson.

Consolidation of what has been learned. Oral dictation.

If you agree with the statement, clap your hands. Express your disagreement with silence.

Statements:

1. Chemical fibers are divided into two groups: artificial and synthetic.

2. Raw materials for the production of artificial fibers are minerals: oil, coal, gas.

3. The raw materials for the production of synthetic fibers are: spruce chips, waste from cotton processing.

4. The technology for obtaining threads of chemical fibers is unified and simple:

Raw materials + solvents = viscous mass.

Formation of threads through filters.

Treatment of threads with hardener, washing.

Winding into bobbins.

5. Chemical fibers are light, beautiful, dry quickly.

6. Less money and time are spent on obtaining chemical fibers - they are more economical.

7. Synthetic fibers have very high hygienic properties: hygroscopicity.

8. When making fabrics, it is undesirable to combine chemical fibers with natural ones, since they are incompatible.

9. Chemical fiber fabrics have low strength.

10. Whether chemical fibers are mixed with natural ones (to improve the properties of fabrics).

Reflection: conversation.

What new and interesting (unexpected) did you learn at the lesson?

How will this knowledge help you in your life?

Summing up the lesson.

Analysis of student responses. Giving marks for class work.

Issuing homework.

Complete the creative task "The use of fabrics from chemical fibers in everyday life" (making crafts - a layout "Ball dress"; curtains; panels, etc.)

To draw the attention of students to the special properties of fabrics made from chemical fabrics: splendor, stiffness of the fabric, waterproofness, transparency. Demonstration of samples from the Teacher's Methodological Fund (works of students of previous years).

Annex 1

Information material 1

"Chemical fibers, their properties. Technology of production of chemical fibers»

In the modern world, more and more fabrics are made from chemical fibers. Rarely in the wardrobe of a modern person can you find a thing made only from natural fibers. Nowadays, almost all natural fabrics contain additives that improve their physical and mechanical properties. They were man-made chemical fibers. However, it should be noted the decrease in hygienic properties.

Chemical textile fibers are obtained by processing miscellaneous by origin of raw materials.

On this basis, they are divided into two groups:

Artificial (viscose, acetate, copper-ammonia);

Synthetic (polyester, polyamide, polyacrylonitrile, elastane).

Stages of obtaining a chemical fiber.

Stage I: Obtaining a spinning solution.

For artificial fiber: Dissolution of pulp in alkali.

For synthetic fiber: addition of chemical reactions of various substances.

Stage II: fiber formation.

Passing the solution through the dies.

The number of holes in the die is 24-36 thousand.
The solution hardens, forming solid thin filaments.

Stage III: Fiber finish.

The threads are washed, dried, twisted, treated with high temperature.

Bleach, dye, treat with a soap solution.

Characterization of the properties of fabrics made of chemical fibers

Fabric properties	Indicators of fabric properties
	viscose	acetate	capron	lavsan	nitrone
Physical and mechanical:
Strength	decreases when wet	Less than viscose, decreases when wet	Very high
Wrinkle		small	small
Drapeability
Hygienic:
Hygroscopicity
Breathability			Minor
Water permeability
Heat shields	Low	Less than viscose			Very high
Technological:
		small
Thread spreading			Significant
shattering			Significant		Minor
wear resistance

Annex 2

Information material 2

Advantages of chemical fibers

Benefit Name	Description
Wide resource base.
High profitability of production	Cotton fiber, for example, grows only 3-4 cm in three months, while chemical fibers are obtained at a speed of hundreds of meters per minute. The following figures speak of the greater economic efficiency of the production of such fibers: it takes 200 working days to produce a ton of cotton, 400 working days to produce a ton of flax, and only 50 working days to produce a ton of viscose fiber.
Independence from climatic conditions.	To get a lot of wool, you need huge pastures for sheep. To grow cotton, flax, etc., fertile soils are required. To obtain natural silk, plantations of mulberry trees are needed. In all these cases, the collection of products is highly dependent on drought and rain, late or early spring, on the time of the onset of autumn and frost. The production of synthetic fibers can be organized in almost any area, and it is not affected by weather conditions.
Many chemical fibers also have the best mechanical properties.	Fabrics made from these fibers have high strength, elasticity, wear resistance and less wrinkling. That is why blended fabrics appeared: natural fibers are combined with chemical fibers to improve the properties of fabrics.
Availability new properties, impossible for natural fibres.	In the 60-70s. created chemical fibers from polymers with specific properties, for example: heat-resistant fibers (from aromatic polyamides, polyimides, etc.) that can withstand long-term operation at 200-300 ° C; heat-resistant carbon fibers, chemical fibers obtained by carbonization and having high heat resistance (in oxygen-free conditions up to 2000 ° C, in oxygen-containing environments up to 350-400 ° C); fluorine fibers (from fluorine-containing carbon-chain polymers), stable in aggressive environments, physiologically harmless, with good anti-friction and electrical insulating properties. Some of these fibers are also characterized by higher than conventional chemical fibers, strength, modulus, greater extensibility, etc. However: the lack of some chemical fibers, such as polyacrylonitrile, polyester, - low hygroscopicity.

Chemical fibers are fibers created artificially through physical and chemical processes.

The production of chemical fibers has a great influence on the development of the textile industry - the range of fabrics is significantly expanded, their properties are improved, new types of fabrics are created due to a mixture of various fibers, etc. There is a constant increase in the production of fabrics from chemical fibers.

This is because:

1. many chemical fibers in their physical, mechanical and hygienic properties are not inferior to natural, and often surpass them;
2. fibers can be obtained with desired properties;
3. the cost of producing chemical fibers is much lower than the production of natural fibers.

Depending on the type of feedstock, chemical fibers can be artificial or synthetic.

artificial fibers

Artificial fibers are produced from wood, cotton cellulose. The fiber production process consists of the preparation of cellulose (drying, treatment with a solution of caustic soda in which it swells, soluble impurities are simultaneously removed), obtaining a spinning solution (dissolving the mass in alkali and obtaining a viscous solution), spinning and finishing fibers.

Fiber spinning

The viscous solution is fed through pipeline 1 to the spinning machine.

1 - pipeline;
2 - piston pump;
3 - filter;
4 - die;
5 - precipitation bath;
6.7 - spinning discs;
8 - funnel;
9 - centrifuge.

Under the pressure created by the piston pump 2, the solution passes the filter 3 and is forced through the spinneret 4 into the precipitation bath 5 containing an aqueous solution of sulfuric acid. The die is a cap made of anti-corrosion metal, having 24-36 holes with a diameter of 0.07-0.08 mm. When a viscous solution and sulfuric acid interact, cellulose is reduced, its streams harden, forming solid thin filaments.

On centrifugal spinning machines, elementary threads are combined into one complex thread, which passes through a system of spinning disks 6 and 7, is pulled out, enters through a funnel 8 into a rotating centrifuge 9. The thread is wound on a bobbin.

Finishing

Finishing consists of a number of operations: washing (to remove sulfuric acid), bleaching, treatment with a soap solution to make the fibers soft and friable, etc.

Artificial fibers are obtained in the form of a complex thread and. A feature of the production of staple fiber is the use of larger dies, with a number of holes of 1600 - 12,000. The threads from each die are connected into a common bundle, which, after finishing operations, enters the cutting machine, where it is cut into short pieces.

"Serving labor", S.I. Stolyarova, L.V. Domnenkova

Fabrics made of artificial and synthetic fibers are widely used both in everyday life and in industry. Lining fabrics (twill, lining satin), dress fabrics (crepe marauquen, taffeta), shirt fabrics (plaid, pique), linen fabrics (linen), as well as decorative and raincoat fabrics are made from viscose threads. In a mixture with cotton, chemical fibers are used for the production of linen knitwear, sportswear. Acetate fibers go...

Chemical fibers include those created in the factory by forming from organic natural or synthetic polymers or inorganic substances. Artificial fibers are obtained from high-molecular compounds found in finished form (cellulose, proteins). Synthetic fibers are produced from high molecular weight compounds synthesized from low molecular weight compounds. They are divided into heterochain and carbochain fibers. Heterochain fibers are formed from polymers, in the main molecular chain of which, in addition to carbon atoms, there are atoms of other elements. Fibers are called carbon chain fibers, which are obtained from polymers that have only carbon atoms in the main chain of molecules.

The prototype of the process of obtaining chemical threads was the process of formation of a thread by a silkworm when curling a cocoon. existed in the 80s. nineteenth century The not entirely correct hypothesis that the silkworm squeezes the fiber-forming liquid through the silk glands and thus spins the thread formed the basis of the technological processes for the formation of chemical threads. Modern methods of forming threads also consist in forcing initial solutions or polymer melts through the thinnest holes of spinnerets.

The production of man-made fibers consists of five main stages: obtaining and pre-treatment of raw materials, preparation of a spinning solution or melt, formation of threads, finishing and textile processing. Artificial fibers are obtained from various natural raw materials - wood, cotton waste, metals, which are purified or converted into new high-molecular compounds during pre-treatment.

To obtain synthetic fibers, the initial raw materials are gases, oil, coal, the products of which are used for the synthesis of fiber-forming polymers.

Obtaining and pre-treatment of raw materials for artificial fibers and threads consists in its purification or chemical transformation into new polymer compounds. Raw materials for synthetic fibers and threads are obtained by synthesizing polymers from simple substances at chemical industry enterprises. This raw material is not pre-treated.

Preparation of spinning solution or melt. In the manufacture of chemical fibers and threads, it is necessary to obtain from a solid initial polymer long thin textile threads with a longitudinal orientation of macromolecules, i.e. it is necessary to reorient polymer macromolecules. To do this, it is necessary to transfer the polymer to a liquid (solution) or softened (melt) state, in which intermolecular interaction is disturbed, the distance between macromolecules increases, and it becomes possible for them to move freely relative to each other. Solutions are used in the production of artificial and some types of synthetic threads (polyacrylonitrile, polyvinyl alcohol, polyvinyl chloride). From the melts, heterochain (polyamide, polyester) and some carbon chain (polyolefin) fibers and threads are formed.

The spinning solution or melt is prepared in several stages.

The dissolution or melting of the polymer is carried out in order to obtain a solution or melt of the desired viscosity and concentration.

Mixing of polymers from different batches is performed to increase the homogeneity of solutions or melts in order to obtain fibers that are uniform in properties throughout their length.

Filtration is necessary to remove mechanical impurities, undissolved polymer particles from a solution or melt, in order to prevent clogging of spinnerets and improve fiber properties; by repeated passage of the solution or melt through the filters.

Deairing consists in removing air bubbles from the solution, which, when they enter the holes of the spinnerets, break off with a stream of solution and prevent the formation of fibers; carried out by holding the solution for several hours under vacuum. The melt is not subjected to deaeration, since there is practically no air in the molten polymer mass.

Thread formation. It consists in the dosed forcing of the spinning solution or melt through the holes of the spinnerets, the solidification of the flowing streams and the winding of the resulting threads on the receiving devices. The jets are formed into elementary filaments from the solution. When forming from the melt, the filament streams flowing from the spinneret are cooled in the blowing shaft by a stream of air or an inert gas. When formed from a solution in a dry way, the streams of polymer are treated with a jet of hot air, as a result of which the solvent evaporates and the polymer hardens. In the case of formation from a solution by a wet method, a stream of thread from the spinnerets enters the solution of the precipitation bath, where the physicochemical processes of the isolation of the polymer from the solution and sometimes chemical changes in the composition of the original polymer take place. In the latter case, one or two baths are used to form the thread.

When forming, either complex threads are obtained, consisting of several long elementary threads, or staple fibers - segments of threads of a certain length. To obtain complex textile threads, the number of holes in the filter can be from 12 to 100. The threads formed from one spinneret are connected, drawn and wound.

Chemical fibers and threads immediately after formation cannot be used for the production of textile materials. They require additional finishing, which includes a number of operations.

Removal of impurities and contaminants is necessary in the production of viscose, protein and some types of synthetic threads, formed by the wet method. This operation is carried out by washing the threads in water or various solutions. The bleaching of threads or fibers, which are subsequently dyed in light and bright colors, is carried out by treating them with optical brighteners.

Drawing and heat treatment of synthetic threads are necessary to rebuild their primary structure. As a result, the threads become stronger, but less stretchable. Therefore, after drawing, heat treatment is carried out to relax internal stresses and partially shrink the threads. Surface treatment (aviation, sizing, oiling) is necessary to give the threads the ability for subsequent textile processing. With this treatment, slip and softness increase, surface bonding of elementary filaments and their breakage decrease, electrification decreases, etc.

The drying of threads after wet formation and treatment with various liquids is carried out in special dryers.

Textile processing. This process is intended for connecting threads and increasing their strength (twisting and fixing the twist), increasing the volume of the thread roll (rewinding), assessing the quality of the resulting threads (sorting).

One of the main directions for expanding and improving the range of chemical fibers is the modification of existing ones to give them new predetermined properties.

Since ancient times, for the production of fabrics, people used those fibers that nature gave them. At first, these were fibers of wild plants, then fibers of hemp, flax, and also animal hair. With the development of agriculture, people began to grow cotton, which gives a very durable fiber.

But natural raw materials have their drawbacks, natural fibers are too short and require complex technological processing. And, people began to look for raw materials from which it would be possible to obtain fabric in a cheap way, warm like wool, light and beautiful like silk, practical like cotton.

Today chemical fibers can be represented as the following diagram:

Click on the picture to enlarge it

Now more and more new types of chemical fibers are being synthesized in laboratories, and not a single specialist can enumerate their vast multitude. Scientists managed to replace even wool fiber - it is called nitron.

1. The production of chemical fibers includes 5 stages:
2. Receipt and pre-treatment of raw materials.
3. Preparation of spinning solution or melt.
4. Thread forming.
5. Finishing.
6. Textile processing.

Cotton and bast fibers contain cellulose. Several methods were developed to obtain a solution of cellulose, forcing it through a narrow hole (die) and removing the solvent, after which threads similar to silk were obtained. Acetic acid, alkaline copper hydroxide solution, sodium hydroxide, and carbon disulfide were used as solvents. The resulting threads are named accordingly:

• acetate,
  

• copper ammonia,
• viscose.

When molded from a solution by the wet method, the streams fall into the solution of the precipitation bath, where the polymer is released in the idea of ​​the finest filaments.

The large group of filaments emerging from the spinnerets is drawn, twisted together, and wound as a complex filament onto a cartridge. The number of holes in the spinneret in the production of complex textile yarns can be from 12 to 100.

In the production of staple fibers, the spinneret can have up to 15,000 holes. A flagellum of fibers is obtained from each spinneret. The tows are connected into a tape, which, after pressing and drying, is cut into bundles of fibers of any given length. Staple fibers are processed into yarn in their pure form or mixed with natural fibers.

Synthetic fibers are made from polymeric materials. Fiber-forming polymers are synthesized from petroleum products:

• benzene
• phenol
• ammonia, etc.

By changing the composition of the feedstock and how it is processed, synthetic fibers can be given unique properties that natural fibers do not have. Synthetic fibers are obtained mainly from the melt, for example, fibers from polyester, polyamide, pressed through spinnerets.

Depending on the type of chemical raw material and the conditions of its formation, it is possible to produce fibers with a variety of predetermined properties. For example, the stronger you pull the jet at the moment it exits the spinneret, the stronger the fiber is. Sometimes chemical fibers even outperform steel wire of the same thickness.

Among the new fibers that have already appeared, one can note fibers - chameleons, the properties of which change in accordance with changes in the environment. Hollow fibers have been developed into which a liquid containing colored magnets is poured. Using a magnetic pointer, you can change the pattern of a fabric made from such fibers.

Since 1972, the production of aramid fibers has been launched, which are divided into two groups. Aramid fibers of one group (nomex, conex, phenylone) are used where resistance to flame and thermal effects is required. The second group (Kevlar, Terlon) has high mechanical strength combined with low weight.

High mechanical strength and good resistance to chemicals are ceramic fibers, the main form of which consists of a mixture of silicon oxide and aluminum oxide. Ceramic fibers can be used at temperatures around 1250°C. They are distinguished by high chemical resistance, and radiation resistance allows them to be used in astronautics.

Table of properties of chemical fibers

		crimp	Strength	Wrinkle
Viscose					burns well, gray ash, burnt paper smell.
Acetate			decreases when wet	less than viscose	quickly burns with a yellow flame, a melted ball remains
				very small	melts to form a solid ball
				very small	burns slowly, forms a solid dark ball
				very small	burns with flashes, a dark influx is formed

The 19th century was marked by important discoveries in science and technology. A sharp technical boom affected almost all areas 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, a fiber made using chemical reactions was first obtained in France. 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 with the help of chemical reactions. Synthetic fibers use synthetic polymers as raw materials, while the processes for obtaining fabrics are not fundamentally different. Inorganic fibers include a group of mineral fibers that are obtained from inorganic raw materials.

As a raw material for artificial fibers, hydrated cellulose, cellulose acetate and protein polymers are used, for synthetic fibers - carbochain and heterochain polymers.

Due to the fact that chemical processes are used in the production of chemical fibers, the properties of the fibers, primarily mechanical, can be changed 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 strengths;
• 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 quite 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 chemical fibers has great advantages over natural fibers:

• firstly, their production does not depend on the season;
• secondly, the production process itself, although quite complicated, is much less laborious;
• thirdly, it is an opportunity to obtain a fiber with pre-set parameters.

From a technological point of view, these processes are complex and always consist of several stages. First, the raw 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:

• use of wet, dry or dry-wet mortar;
• application of metal foil cutting;
• drawing from a melt or dispersion;
• drawing;
• flattening;
• gel molding.

Application of chemical fibers

Chemical fibers have a very wide application in many industries. Their main advantage is relatively low cost and long service life. Fabrics made from chemical fibers are actively used for tailoring special clothes, in the automotive industry - for strengthening tires. In the technique of various kinds, non-woven materials made of synthetic or mineral fibers are more often used.

Textile chemical fibers

Gaseous products of oil and coal refining are used as raw materials for the production of textile fibers of chemical origin (in particular, for the production of synthetic fibers). Thus, fibers are synthesized that differ in composition, properties and combustion method.

Among the most popular:

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

Among the 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 waste from cotton production, so they absorb moisture well.

Chemical fiber nonwovens

Nonwoven materials can be obtained from both natural and chemical fibers. Often non-woven materials are produced from recycled materials and waste from other industries.

The fibrous base, prepared by mechanical, aerodynamic, hydraulic, electrostatic or fiber-forming methods, is fastened.

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

1. Chemical or adhesive (adhesive)- the formed web is impregnated, coated or sprinkled with a binder component 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 material are used, but in most cases a small amount of fibers with a low melting point (bicomponent) is deliberately added to the nonwoven material at the spinning stage.

Chemical fiber industry facilities

Since the chemical production covers several industries, all chemical industry facilities are divided into 5 classes depending on the raw materials and application:

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

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