Chemical production - a major source of human wealth.After all, everything from household items to clothes, performed and produced on the basis of the science.
special role assign different chemical fibers, which are used in many fields of science, technology and industry.
Classification of chemical fibers
All chemical fibers can be divided into two large groups.
- Artificial - are those which are based on natural polymer, but the handling and molding directly filaments occurs with the participation of physical and chemical methods.
- Synthetic - fibers that are created directly in the laboratory (industrial) conditions.They are based on the usual low molecular weight compounds that are converted to macromolecules in the polymerization reaction.
In turn, artificial and synthetic fibers also have their classification and examples.Consider the one for the synthetic samples.
They can be divided into two large groups.The underlying structure of the carbon chain, and methods of forming relationships.
- carbochain synthetic fibers. main chain is built strictly of carbon atoms linked together by conventional sigma-type connections.This group can be attributed quite a large number of samples.For example, polyacrylonitrile, polyethylene, polyvinyl chloride, polypropylene, polyvinyl alcohol.
- hetero synthetic fibers. characterized by including a hetero macrochain carbon - nitrogen, sulfur, phosphorus and others.This group includes such fibers: polyester, polyurethane, polyamide.
If we talk about the use of it in the textile industry, the value of the described representatives of different.So, man-made fibers is much more useful for clothing, bedding, towels and other household linen items.Although there are exceptions, when such fabric is used in the art.
synthetic chemical fibers, on the other hand, much more relevant in the construction, engineering, industry, rather than at home.More precisely, consider polyester filament fabrics from them and applications.
Fibers made of polyester: general characteristics
From a chemical point of view, the product - the result of the interaction of terephthalic acid and ethylene glycol S8N6O4, diol S2N6O2.As a result, the polymerization reaction of the complex forms a clear or white crystals, has an important property - viscosity.To do this, they heat up.It is based on this feature to obtain directly from the fibers of the substance.
melting point of these materials is greater than 260 0C.This makes them very comfortable in applying for technical purposes.There are a number of special properties possessed by such fibers.
- polyester synthetic fibers can withstand acids, alkalis.
- It does not dissolve in water, solvents, organic nature.
- is an insulator, that is practically do not conduct electricity.
- products are robust, very durable and reliable.
Being completely synthetic in nature, these strands is largely superior to the technical characteristics of the textile and many man-made fibers.
production method
According to the previous description, the basis for the production of polyester must be terephthalic acid.However, its physical properties are somewhat inconvenient for harmonious and rapid polymerization reaction with ethylene glycol, so it is not used in pure form, as an ester.Its name - the same name broadcast dimetiltereftalevy acid, abbreviated as DMT.
Therefore, the production of polyester fiber is composed of several sequential chemical steps:
- oxidation of para-xylene and a mixture of esters, ie the preparation of starting materials;
- esterification, ie the production of ester DMT;
- distillation and purification of the resulting product;
- recrystallization of DMT in order to obtain raw material.
Prepared under the scheme stuff is ready to join the next cycle of reactions that result and will Polyester (Polyester).This takes place in two main stages.
- received DMT transesterification with ethylene glycol.Result - diglycol and low molecular weight polyesters.
- Polycondensation obtained in the first stage of the products among themselves.The result is a viscous polietilentereftalatat.
Now it's the technical side.The substance is passed through a special small spinneret prodavlivaya like, and thus prepared fiber.Upon cooling they crystallize.Further processing is pulled, purification and coloring.
material
names in different countries produced and used such fibers.Polyester synthetic fibers in each state got its name, so have a lot of synonyms.Let us see what they are.
- in Russia - polyester, polyether, polyester.
- In America - Dacron.
- United Kingdom - Terylene.
- Japan - teteron.
- France - tergalii.
However their any name and properties remain the same and the application too.
Material Polyester: Properties
to main positive sides Dacron should include such features as:
- bad creasing;
- flammability;
- lightfastness;
- wear;
- strength and softness, smoothness;
- resistance to most organic solvents, and acids and alkalis;
- lack of abrasion;
- fabric does not support the development of living organisms (fungi, mites, bacteria, etc);
- impact;
- tensile strength.
course, a set of positive performance can not go unnoticed.That is why the application of polyester products is very broad, covering most sectors of the economy.
However, there are drawbacks.These include the following points:
- are difficult to color, so rich and bright colors in these tissues does not occur;
- highly electrified, as dielectrics themselves;
- if you take the real, not processed by special methods polyester, it will be tough enough material.
All these shortcomings are easily eliminated additives of certain substances in the production of fiber.Therefore, significant values they have.
hollow fibers
This type of polyester yarn is very important in the construction and engineering and is used there.Although there are exceptions.For example, such as hollofayber who found refuge in the textile industry.
hollow fibers used for the manufacture of:
- fiberglass;
- building materials;
- thermal insulation of things;
- radio products.
They are used as filters in wastewater treatment.Hollofayber due to its characteristics in general have long been supplanted natural feather and down from the textile industry.He became the main type of filler pillows, blankets, clothes and other things.
Ball Polyester fiber
This is a basic product for the manufacture of most soft, environmentally friendly and non-allergenic bedding.Such fibers are used as fillers for blankets and pillows.
Why use them?This is due to excellent technical characteristics.
- not absorb moisture.
- elastic.
- amenable to machine washing, simple and easy to care for and use.
- are odorless.
- not cause allergies.
- They are indispensable for the development of micro-organisms.
This gives spherical Polyester fiber as a filler of furniture, bedding and clothing clear advantage over natural natural "counterparts": down, feather.
The disadvantage is a shorter life compared to natural materials.However, the cost of these products is much lower.
staple fiber
include polyester fibers such a special place is its variety as staple yarn.It is their plant produces synthetic fibers to a greater extent than others.This is because such a product is manufactured directly on the yarn, and then the material for clothing, textiles and so on.
often called staple fibers formed from the harmonious combination of wool or cotton and polyester.This symbiosis allows you to receive the following types of materials:
- costume;
- Coat;
- lace;
- of shirts;
- curtain;
- dress;
- felt;
- carpet;
- fur.
Obviously, some products can be sewn and made of such components.
technical polyester thread
These fibers are used to make the following kinds of products:
- fishing nets and trawls;
- ropes and ropes;
- hoses for petroleum products;
- canvas;
- conveyor belt;
- seat belts and power transmission belts;
- tire cord;
- of insulation and filter materials.
These strands can be attributed discussed above hollow fiber.
Production of polyester materials
What other products can be made from polyester?The special significance of such materials, which are used as a filler, we have described above.I would like to add that hollofayber lets get the pillow soft and comfortable and warm and a light blanket.Polyester fiber in the textile business is simply irreplaceable, and every year on the value rises higher and higher.
also use Dacron to prepare the following types of fabrics:
- taffeta;
- crepe;
- jersey;
- crimplene;
- Mel.
of them made clothes, tulle and curtains, scenic attributes, and so forth.
Another type of practical human activity, which are used in polyester - is surgery.Medicine examined the possibility of producing artificial blood vessels and surgical threads of polyester.This, of course, facilitates many operations to save lives.
Reviews of products and this fiber
Given that, in addition to the positive characteristics, polyester-based materials still have disadvantages, not all people are satisfied with the products.When it comes to building applications, there can be no dispute: Dacron - the leader.However, speaking of textile products and clothing, it should be noted and differences.Negative opinions are also consistently receives polyester fiber.Reviews of this kind are based on the shortcomings of the fabric - electrified and limited life.
However, most people tend to assume polyester one of the most comfortable, beautiful and high-quality materials of our time.Therefore, clothes, household items and bedding made from these materials only become popular over the years.
If you look at reviews of pillows and blankets on the basis of polyester, the vast majority of them will still be positive, which is quite justified and fair.
