Nylons development

In Europe, 1. G. Earbenindustrie decided to develop nylon-6 that had been synthesized from S-caprolactam using an aminocaproic acid catalyst (1) and commercially introduced as Pedon L in 1940 (11,12). 1. G. Earbenindustrie had evaluated over 3000 polyamide constituents without finding an improvement over nylon-6 and nylon-6,6 (13). In Italy, Societa Rhodiaceta started making nylon-6,6 in 1939. In the United Kingdom, ICl and Courtaulds formed British Nylon Spinners in 1940 and started to manufacture nylon-6,6 in 1941. 

Polyamides are the second largest group of synthetic fibers after polyesters. However, they were the first synthetic fibers that appeared in the market in 1940. This was the result of the work of W. H. Carothers in USA who developed nylon 66. At about the same time nylon 6 was also developed in Germany by I. G. Farben. Both of these nylons still dominate the market for polyamides. However, due to patent restrictions and raw materials considerations, nylon 66 is most extensively produced in USA and nylon 6 is most extensively produced in Europe. 

With nylon evolving from a scientific to an engineering problem, Carothers basic research department became a division devoted to developing nylon. Since few engineers knew anything about polymers, several of Carothers assistants moved into engineering and development. Only a skeleton crew, including Flory, Coffman, and Berchet, remained to work for Carothers on theoretical or exploratory problems. 

Carothers (du Pont) synthesizes the first aliphatic polyesters, establishes the principles of step-growth polymerization, and develops nylon 6,6 Julius Nieuwland develops the synthetic mbber called neoprene Poly(methylmethacrylate) (PMMA) is synthesized Hans von Chain and Sir Frank Whittle file patents for the jet engine Cathode ray tubes (CRTs) are invented by Allen B. Du Mont Ernest Ruska discovers the electron microscope magnification of 12,000 X... 

The discovery of nylon is one example. In 1928, E.l. DuPont de Nemours and Company appointed a young, 32-year-old chemist from Harvard, Wallace Carothers, as the director of its new research center. The goal was to create artificial fibers similar to cellulose and silk. In 1930, Julian Hill, a member of Carothers team, dipped a hot glass rod in a mixture of solutions and unexpectedly pulled out long fibers such as the one shown in Figure 1-14. Carothers pursued the development of these fibers as a synthetic silk that could withstand high temperatures and eventually developed nylon in 1934. Nylon s first use was in a toothbrush with nylon bristles. During World War 11, nylon was used as a replacement for silk in parachutes. Nylon is used extensively today in textiles and some kinds of plastics. 

The 1930s saw the introduction of the poly generation and the first of many such thermoplastics was poly(vinyl chloride) or PVC which became commercial reality with the introduction of a plasticiser. At about the same time Du Pont Chemicals also launched the polyamide nylon 66 after studying the network structure of silk. A few years later German researchers developed nylon 6 from caprolactam. In the UK, ICI developed and produced polyethylene, a material vital to the success of radar technology during the Second World War. ICI also made a valuable wartime contribution with the development of poly(methyl methacrylate) or PMMA which was used to make shatterproof and protective screens. 

Caprolactam melts at about 69°C. It does not polymerize upon heating to elevated temperatures. However, shortly after Carothers developed nylon-6,6, Schlack [51] of I.G. Farben discovered that the ring-opening reaction occurs readily in the presence of amine and carboxyl groups. Thus, -aminocaproic acid, nylon-6,6 salt, or simply water, is employed to hydrolyze lactam to form [COOH] and [NH2] end groups. The [COOH] group catalyzes the addition of [NH2] to the caprolactam ring. This discovery led to the polymerization of caprolactam for nylon-6. 

Wallace Hume Carothers, 1896-1937. American chemist who developed nylon, the first synthetic macromolecular fiber at the du Pont de Nemours Company in Wilmington, DE. 

Synthetic rubber (Wallace Hume Carothers) Carothers synthesizes rubber and goes on to develop nylon in 1935. His work professionalizes polymer chemistry as a scientific field. 

Nylons were introduced to the market in the late 1930 s. Of the various types, nylon 66 was the first. As is well-known, this product was developed by the DuPont Company as the first truly synthetic fiber with a broad range of applications. Soon after, about 1939/1940 nylon 6 fibers were introduced by the I.G. Farbenindustrie in Germany. Simultaneously, however, the I.G. also developed nylon 6, nylon 66, and nylon copolymers for plastics use. 

Picking up again with the same people who developed Nylon 11,... 

The immediate spectacular success of nylon 6,6 led to an intensive search throughout the world for competitive fibre-forming polymers not covered by the du Pont patents. As a result of such work, I. G. Farbenindustrie (Germany) developed nylon 6 production was started in 1940. After the Second World War, the manufacture of nylon 6 was undertaken in many countries since it was free from patent restrictions. At the present time nylons 6,6 and 6 account for nearly all of the total output of polyamides for fibre production. 

The development of the two ferroelectric and piezoelectric polymers - PVF2 and odd-numbered nylons - provides a possibility to make all polymer ferroelectric and piezoelectric composite system. Using PVDF and nylon 11, Su et al. developed nylon ll-poly(vinylidene fluoride) bilaminates by a co-melt-pressed-stretched process in 1992 (Su et al.). The bilaminate exhibits a typical ferroelectric D-E hysteresis... 

Research continued into fiber-forming polymers, but the next new fully synthetic yam was not discovered until the 1930s, when Wallace Hume Carothers, working for DuPont, discovered and developed nylon. This was first commercialized in 1938 and was widely developed during the 1940s to become one of the major yam types used. Continuing research led to the discovery of polyester in 1941, and over the ensuing... 

In the 1930s, W. H. Carothers, an American chemist, and his associates at E. I. DuPont de Nemours Company in Wilmington, Del., developed nylon, the first synthetic polymer fiber to be produced commercially in 1938. These findings laid the foundations of the synthetic-fiber industry. 

Flory, Paul John (1910-85) American polymer chemist. Flory s early work consisted of helping Wallace CAROTHERS to develop nylon and neoprene. He began to investigate the properties of polymers in the 1930s. Flory solved the difficulty that a polymer molecule does not have a fixed size and structure by using statistical techniques to calculate a distribution of polymer chain lengths. Flory also worked on polymers in which there are links between chains. This led to work on the elasticity of rubber. Flory summarized his work in the classic books Principles of Polymer Chemistry (1953) and Statistical Mechanics of Chain Molecules (1969). Flory won the 1974 Nobel Prize for chemistry for his work on polymers. 

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