Silk thread is stronger than usual.
Silk thread is very durable. In order for her to make even stronger, silkworms are fed with carbon nanotubes and graphene.
Silk thread is a natural material made from fibers obtained from the cocoon of the silkworm eating the leaves of the mulberry tree and hanging around a durable cocoon.
Silk fiber consists of 75% fibroin and 25 % of sericin (the natural glue of the tracks). In addition to the fibroin and sericin in silk contains waxes and fats and mineral substances. If we consider the fiber under a microscope, you will notice two parallel strands of gut nuggets with a touch of sericin on them. The thickness of the filament is 20-30 micrometers. Its length from one cocoon reaches 400-1500 m. by Itself, a silk thread is strong enough. The breaking stress of silk thread is approximately 40 kgf/mm2 (40х107н/m2), elongation 14-18%. The thread has a triangular cross-section and, like a prism, refracts the light that is beautiful and Shine transfusion.
Silk thread – fine natural fiber which is of high quality. It is a huge success due to its unique properties. Silk can be easily dyed, soaking up the saturation and brightness of the paint. The resulting color has the ability to sparkle, changing shades under different lighting. Silk thread is one of the most durable materials. Strength is not inferior to steel wire with the same cross-sectional diameter.
It is believed that the production of silk originated in ancient China, during the reign of Yellow Emperor Huang Di. Numerous archaeological excavations undertaken in various Chinese provinces, showed that the secret of making silk was known in the days of the Neolithic culture. Discovered written records, in the form of characters with the characters of silk, the mulberry tree and a cocoon and these cocoons, and even the surviving fragments of silk products.
By the middle of the 1st Millennium BC, about six of the United States on the territory of modern China had its own production of silk yarn, fabrics and products. The secret of growing caterpillars and production of silk zealously defended. A strict ban was imposed on the manufacture of silk, the export of seeds and shoots of the mulberry tree and the silkworm: from larvae to cocoons. Any violation of this prohibition led the offender to the death penalty. In the 2nd century BC was built the Great silk road – caravan route, which connected East Asia to the Mediterranean. The main product of the caravans coming from Asia, it was silk. Despite the fact that for thousands of years China was the exclusive manufacturer of this material in 300 ad the secret of silkworm breeding and the production of filaments from the cocoons took control of Japan, and later on in the year 522 Byzantine and some Arab countries. Subsequently, during the Crusades, “silk secret” came to Europe.
The painstaking process of silk production consists of several stages.
Themselves produces silk thread silkworm. Today, the domesticated silkworm are grown on special farms. Many breeding varieties differ in their ability to live and breed in different conditions, and frequency of reproduction. Some species give birth once a year, others can give a few offspring within one year.
The production process begins with the mating after which the female moths in a few days lay eggs. It is able to defer for the time from 300 to 600 eggs. These eggs are collected, sorted and then placed in incubators with a certain humidity and a temperature of +24, +25 °C for 8-10 days. After which are born dark brown larvae, up to 3 mm in length, which stand in a well ventilated room where the special trays they begin to actively feed on fresh leaves of mulberry tree.
For 40 days and nights of continuous meal of mulberry silkworms increase their weight 10,000 times, turning into a light pearl-colored caterpillar with a large jaw on a big head, reaching a length of up to 8 cm and 1 cm in diameter. At this stage the caterpillars are placed in special boxes, where they begin to create around himself a dense network of fine silk is the only filament of saliva, which is called a cocoon. This process lasts for 3-4 days.
Ready, the cocoons are collected, put into boiling water and carefully unwound fiber (econometrie). Then a special brush find the thread end and depending on the desired thickness, the threads are rolled for the machine for two or more at once, and reeled into skeins. It is raw silk, paint it yellowish-opaque. After processing by special glue silk gloss.
This yarn is sent to the weaving factory where it is bleached or dyed and then produce tissue. In General, dye the silk in skeins of thread, and the finished fabric. To add Shine and richness of color, raw materials are treated in vinegar.
And finally comes the process of decamerone, when the silk strands are treated with high pressure steam for several minutes.
– strength. This elastic material is durable at the same time, as wire, which is achieved in the production of various methods of twisting fibers. Silk is widely used in surgery, microsurgery as a suture material. In ancient times soldiers wove silk armor that did not allow the arrows to penetrate deep into the body,
is the density. The density structure of the silk fabric close to the paper, so it was used for writing letters
– resistance to deformation. With proper washing silk items don’t decrease in size because a silk thread, stretching out easily, as easily returned to its original state
– wear resistance. Silk items retain excellent appearance for decades
– hygroscopicity. Silk fabric easily absorbs moisture, sweat, and dries quickly. Now in the home for irons steamers are widely used. Due to the property of silk is easy to pass steam through fiber, silk products easy to steam. Therefore, iron the silk better in the wet state,
silk has antibacterial and disinfectant properties, is hygienic. He is able to protect the skin from breeding bacteria, to inhibit the growth of parasites: mites, bedbugs and lice.
– a beneficial effect on the skin. Silk fabric stimulates regeneration processes in the upper layers of the epidermis. Proteins and amino acids, which in large quantities contained in the silk fibers and cocoons of the silkworm, are used extensively in the production of creams to nourish and hydrate the skin as well as care products for the skin, contributing to wrinkles and healing of microcracks. One of the silk protein slowing the aging process of the skin, revitalizes it,
– perfect thermoregulation. The clothing made from silk has the feature of keep warm in cool weather and cool the body during heat.
To make a silk thread stronger, silkworms are fed with leaves sprayed with an aqueous solution containing carbon nanotubes and graphene at a concentration of 0.2%. After eating the leaves the caterpillars weave around themselves a cocoon. In this fiber, from which in the future get a silk thread, is formed from caterpillars, as usual, of two special salivary glands that produce salivary fluid and turning during cooling in a thin and strong thread. Carbon particles (graphene and carbon nanotubes) are embedded into the structure of the fiber and make it more orderly. This fiber is 50% stronger than normal (if you do not feed caterpillars graphene and carbon nanotubes) and in contrast to the usual conducts electric current.
Silk fabric of reinforced fibers of carbon nanomaterials can be used for the production of wear-resistant protective fabrics, and in biodegradable medical devices and wearable electronics.
For information. Scientists conduct various experiments with the diet of silkworms. In their diet, introduce a variety of dyes, antimicrobial additives, titanium oxide (it resulted in ultra-strong fibre, resistant to UV), etc. substances. It is much more efficient than process the finished silk thread.