Lovsan: what is it, basic properties and scope

In the composition of fabrics indicated on the labels of many types of clothing, you can often see the word lavsan. What it is? In addition to being one of the most popular synthetic materials, most people do not know much about it.

What is lavsan?

In scientific terms, it is called polyethylene terephthalate. It is a product obtained by polycondensation of terephthalic acid (DMT) and ethylene glycol. It is a solid that is colorless in the amorphous state, and has a white color in the crystalline state. As a result of the chemical process at a certain temperature, polyester fibers are formed , which have high strength and wear resistance.

Title History

The lavsan material was named after the Laboratory of Macromolecular Compounds of the Academy of Sciences, where it first appeared. The first letters of the name of the laboratory and gave the name to the new substance. In other countries polyethylene terephthalate has different names - dacron in America, tergal in France, trevira in Germany.

In the process of perfecting this material, great merit belongs to E. M. Aizenshtein, under whose guidance the technical thread lavsan, having special properties, was obtained at the time.

Making lavsan

In one of the shops of the plant a chemical reaction occurs, as a result of which the substances DMT and ethylene glycol are converted into a viscous resinous mass. Forming fibers in a spinning shop with the help of special equipment. The resin flows in fine trickles through minute holes. The thickness of the future thread depends on their size. The spinning speed of the fiber is from 500 to 1200 meters per minute. Thin webs are quickly glued into a thread and wound onto a reel.

These fibers are not yet lavender. What it is? So far, the resulting substance can be called an amorphous polymer, which is still unsuitable for the manufacture of articles. At a certain temperature, it is subjected to stretching, then heat fixation with hot air and only then sent to weaving factories and other enterprises.

Threads, which in the future will become wool, are unwound from the bobbin, gathering in bundles. Then they stretch out, corrugate, and the fiber acquires a resemblance to natural wool. The bundles are cut into pieces, the size of which depends on which natural fiber they will be mixed with in the future.

Properties of lavsan fibers

This material has several advantages over polyamide fibers. It is appreciated for its resistance to moisture, light, high temperatures and good elasticity, perfectly retaining folds and pleated hair when washing.

Products made of this material resemble woolen. But, unlike them, they are much stronger, they are not damaged by moth or mold, they do not ignite and are more resistant to abrasion. Lovsan is a fiber that deforms only at temperatures above 260 ° C. It feels great in acidic and slightly alkaline medium.

High crystallinity and small pore sizes do not allow qualitative painting of the material under normal conditions. It is best to do this before forming the fiber or at a high pressure and a temperature of 200 ° C.

Biologically indifferent substance is lavsan. What it is - is well known to medical professionals. This material does not interact with the human body, due to which lavsan threads are widely used in surgery. Unlike conventional surgical threads, they do not deform after surgery and retain the appearance of the suture.

Application of lavsan

In which only the branches of industry and national economy do not find use of the lavsan due to its unique properties! He is particularly in demand in the textile industry for the manufacture of sewing thread, curtain-tulle fabrics, decorative fabrics and artificial fur. Fabric lavsan is successfully used in the production of knitwear, shirts, suits, dresses, etc.

The insulating properties of this material make it indispensable in the electrical industry. Fire hoses, irrigation hoses made of lavsan, can not be rotted and have a very long service life.

There is a great demand for lavsan in medicine. It is used as a substitute for blood vessels. In surgery, the lavsan thread increasingly replaces the usual thread.

Polyethylene terephthalate has found wide application in the field of creation of food films, plastic containers and bottles. In addition, this is the most important component in the manufacture of modern data carriers (disks, films, magnetic tapes).

In the chemical industry, medical and mechanical engineering are not dispensed today without the use of lavsan. It is used in the manufacture of household appliances, food equipment, transport belts. Filling polyethylene terephthalate with various additives (glass fiber, fluoroplastic, molybdenum disulphide) significantly improves its mechanical and electrical properties. It is difficult to name today the area of production, wherever the lavsan is used. What it is and what properties it possesses has been discussed in detail in the article.