Synthetic silks applications

Chemically modified cellulose in the form of cellulose nitrate or nitrocellulose was made and tested for commercial applications in Britain in the 1855-1860 period without much success. The discovery by Hyatt, in 1863, that cellulose nitrate could be plasticized with camphor to give moldability to the blend, made this material much more useful. By 1870, celluloid (plasticized cellulose nitrate) was being produced into a variety of commercial products such as billiard balls, decorative boxes, and combs. Nitrocellulose was also soluble in organic solvents, unlike cellulose, and so could be applied to surfaces in solution to form a coating, as in airplane dopes and automobile lacquers. It could also be solution spun into fibers (synthetic silk) and formed into photographic film, or used as a laminating layer in early auto safety glass. It was also used as an explosive. The hazard introduced to many of these uses of nitrocellulose by its extremely flammable nature resulted in an interest to discover other cellulose derivatives that could still be easily formed, like nitrocellulose, but without its extreme fire hazard. 

When the boss came back, they told him, and nylon was developed—over a period of 10 years—into a silk-like material. Advertised at the 1939 New York World s Fair as synthetic silk made from coal, air, and water, its application in hosiery for women was demonstrated by a model in a giant test tube. The material was an instant success. Reportedly four million pairs of nylon stockings sold in a few hours in the first New York City sale, but almost immediately sales were restricted and the material commandeered for parachutes. William Carothers did not live to see the success. He died by his own hand in a Philadelphia hotel in 1937. 

Spider-web silk is ca. five times stronger than steel by weight, and almost as elastic as nylon. Fibers comprised of the synthetic silk were demonstrated to be stronger than Kevlar, and may be useful for biomedical applications such as artificial tendons and ligaments and surgery sutures, as well as lightweight body armor for military applications. 

Stannic chloride is also used widely as a catalyst in Eriedel-Crafts acylation, alkylation and cycHzation reactions, esterifications, halogenations, and curing and other polymerization reactions. Minor uses are as a stabilizer for colors in soap (19), as a mordant in the dyeing of silks, in the manufacture of blueprint and other sensitized paper, and as an antistatic agent for synthetic fibers (see Dyes, application and evaluation Antistatic agents). 

Sulfur dyes are used mainly for dyeing textile cellulosic materials or blends of cellulosic fibers (qv) with synthetic fibers such as acrylic fibers, polyamides (nylons), and polyesters. They are also used for silk (qv) and paper (qv) in limited quantities for specific applications. Solubilized sulfur dyes are used on certain types of leathers (qv). 

To extend the application area of silk proteins-based materials, blending the fibroin with other natural macromolecules and synthetic polymers, or even manufacturing composites with silk fibers are a few of the possible strategies. 

The oxidising properties of ozone have led to the application of this gas to the bleaching of such substances as starch, flour, oils, and wax, delicate fabrics, etc. It has been used in the production of artificial silk and synthetic camphor. It has also been used to aid the ageing or maturing of wines, spirits, and tobacco. The action of ozone on unsaturated organic compounds provides a very convenient general method for the preparation of aldehydes and ketones, which has already been applied to the manufacture of vanillin for flavouring purposes and heliotropin for perfumery. 

One can classify fibers in a variety of ways. For example, one may divide the whole field of fibers into apparel and nonapparel fibers, i.e. based upon the final use of fibrous material. The apparel fibers include synthetic fibers such as nylon, polyester, spandex, and natural fibers such as cotton, jute, sisal, ramie, silk, etc. Nonapparel fibers include aramid, polyethylene, steel, copper, carbon, glass, silicon carbide, and alumina. These nonapparel fibers are used for making cords and ropes, geotextiles, and structural applications such as fiber reinforcements... 

Polymers, which include synthetic materials such as plastics, vinyl, Nylon, polyester, and polytetrafluoroethylene (PTFE) and natural materials such as silk, cotton, starch and cellulose, are used in our lives every day. Since scientists began to control and manipulate polymers in the 19th Century, chemists have created hundreds of durable synthetic polymeric materials from just a few simple building blocks. Experimentation continues today with increasing polymer uses for applications in chemical, instrumentation, mechanical, electrical and electronic industries. 

Resistance to axial compressive deformation is another interesting property of the silk fibers. Based on microscopic evaluations of knotted single fibers, no evidence of kink-band failure on the compressive side of a knot curve has been observed (33,35). Synthetic high performance fibers fail by this mode even at relatively low strain levels. This is a principal limitation of synthetic fibers in some structural applications. 

OTHER COMMENTS used as a pharmaceutical aid used as a synthetic flavoring substance useful in the manufacture of smokeless powder, photographic films, artificial leather, artificial silk, and perfumes applications as a solvent for nitrocellulose, varnishes, lacquers, and aeroplane dopes. 

PL A fabrics exhibit the comfort and touch of natural fibres such as cotton, silk and wool while having the performance, cost, and easy care characteristics of synthetics. PLA fibres demonstrate excellent resiliency, outstanding crimp retention and improved wicking compared with natural fibres. Fabrics produced from PLA are being utilized for their silky feel, drape, durability and water vapour permeability used to create breathability suitable for sport clothing applications [195]. 

DoreTex is a yam-spinning company that focuses on high-end yams. While 60% of the company s output is synthetic, the company s core focus is cotton. This is both because the DoreTex production technology is based on the system used for cotton and because the natural fibre, along with linen, hemp, silk, wool and cashmere, is what ensmes the company s privileged relationship with the fashion industry. Consequently, the application of the decision-making process was focussed on the cotton division. 

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