Nylon carothers/DuPont

Poly(vinyl chloride) (PVC) wall covering Cellulose acetate sheet and rods Graft copolymers Nylon (Carothers DuPont)... 

The history of thermoplastic polyester goes back to 1929 with the pioneering work of Carothers. The first aromatic polyester of importance is poly(ethylene terephthalate) commonly abbreviated PET (or PETE) and was prepared by Whinfield and Dickson. In 1941, they created the first polyester fibers called Terylene and first manufactured by Imperial Chemical Industries (ICI). PET was produced commercially in 1953 as fiber for textile industry (Dacron) by Dupont using modified nylon technology. Dupont polyester research rapidly leads to a whole range of trademarked products as Mylar, a strong polyester film. 

History. The most sophisticated work on saturated polyesters is usually traced to W. H. Carothers, who, from 1928 to 1935 with DuPont, studied polyhydroxy condensates of carbolic acids. Unable to achieve suitable heat and chemical resistance from these esters, he turned to polyamide-carboxylic acid reaction products, which later became nylon. Carothers concepts on saturated polyesters yielded several other polyester products such as Terylene, which became patented and introduced in the United States as dacron and mylar. 

The leader of DuPont s effort was Wallace H Carothers who reasoned that he could reproduce the properties of silk by constructing a polymer chain held together as is silk by amide bonds The neces sary amide bonds were formed by heating a dicar boxylic acid with a diamine Hexanedioic acid adipic acid) and 1 6 hexanediamme hexamethylenedi-amine) react to give a salt that when heated gives a polyamide called nylon 66 The amide bonds form by a condensation reaction and nylon 66 is an example of a condensation polymer... 

The best known step-growth polymers are the polyamides, or nylons, first prepared by Wallace Carothers at the DuPont Company by heating a diamine with a diacid. Por example, nylon 66 is prepared by reaction of adipic acid (hexanedioic acid) with hexamethylenediamine (.1.,6-hexanediamine) at 280 °C. The designation "66" tells the number of carbon atoms in the diamine (the first 6) and the diacid (the second 6). 

The polymer in Example 23.4 is Nylon-66 (the numbers indicate the number of carbon atoms in the diamine and dicarboxylic acid molecules). This polymer was first made in 1935 by Wallace Carothers working at DuPont (Figure 23.3). Since then, other nylons, all polyamides, have been synthesized. 

Nylon 66 was the first polyamide to be produced commercially. Developed by Wallace Carothers at the DuPont Chemical Company In 1935, it still leads the polymer industry in annual production. Figure 13-7 illustrates that Nylon 66, made from adipic acid and hexamethylenediamine, is so easy to make that it is often used for a classroom demonstration ... 

In addition to the use of salt combinations to produce nylons described in Chapter 4, nylons may also be produced by the anionic ROP of lactams. In fact, this method was largely developed to overcome patent rights held by DuPont based on the work of Carothers and his group. This is the preferred method for the production of nylon-6, structurally analogous to nylon-6,6, and is widely practiced in Europe. 

In 1928, Speed became a consultant to the DuPont Experimental Station due to the nudging of Roger Adams. Chemistry was on the rise with the invention of the first SR (neoprene) and first truly synthetic fiber (nylon) both discovered by Carothers. The plastics industry developed rapidly with chemistry truly becoming an industrial giant, mainly on the back of giant molecules. 

Wallace Carothers and coworkers at DuPont synthesized aliphatic polyesters in the 1930s [Furukawa, 1998 Hounshell and Smith, 1988]. These had melting points below 100°C, which made them unsuitable for firber use. Carothers then turned successfully to polyamides, based on the theoretical consideration that amides melt higher than esters. Polyamides were the first synthetic fibers to be produced commercially. The polyester and polyamide research at DuPont had a major impact on all of polymer science. Carothers laid the foundation for much of our understanding of how to synthesize polymeric materials. Out of that work came other discoveries in the late 1930s, including neoprene, an elastomer produced from chloro-prene, and Teflon, produced from tetrafluoroethylene. The initial commercial application for nylon 6/6 was women s hosiery, but this was short-lived with the intrusion of World War II. The entire nylon 6/6 production was allocated to the war effort in applications for parachutes, tire cord, sewing thread, and rope. The civilian applications for nylon products burst forth and expanded rapidly after the war. 

Wallace Carothers, the inventor of nylon, stretches a piece of synthetic rubber in his laboratory at the DuPont company. 

Nylon. In 1939 the DuPont Company introduced the first truly synthetic textile fiber. Dr. Wallace Carothers invented nylon as a result of his basic research into polymer science. Chemically, nylon is a polyamide fiber. The two major types of nylon polymer are used in textiles type 6,6 which is made by using hexam-ethylene glycol and adipic acid, and type 6, which is made by polymerizing e-caprolactam. Nylon fibers are made by melt-spinning the molten polymer. The result is a continuous filament fiber of indeterminate length. It is spun in many deniers, with its diameter varying from 10 to 50 microns. The cross-section usually is round, trilobal, or square with hollow channels when used as carpet fiber. 

Nylon was first synthesized at DuPont by Wallace Carothers in the 1930s. After Japanese control of silk production in the South Pacific made silk unavailable to the United States during World War II, nylon was used to replace silk in the manufacture of parachutes. The synthesis and properties of nylon are discussed in Chapter 22. 

One of the most important condensation polymers is nylon, a name so ingrained into our language that it has lost trademark status. It was developed by Wallace Carothers, director of organic chemicals research at DuPont, and was the outgrowth of his fundamental research into polymer chemistry. Introduced in 1938, it was the first totally synthetic fiber. The most common form of nylon is the polyamide formed by the condensation of hexamethylene diamine and adipic acid ... 

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. 

Rayon is a semisynthetic fiber because it is prepared from a natural polymeric starting material. The first truly synthetic polymeric fiber was nylon, developed in the 1930s by the American chemist Wallace Carothers at DuPont Company. He knew of the condensation of an amine with a carboxylic acid to form an amide linkage (see Section 7.6) and noted that, if each molecule had two amine or carboxylic acid functional groups, long-chain polymers could form. The specific starting materials upon which Carothers settled, after numerous attempts, were adipic acid and hexamethylenediamine ... 

He was bom in Iowa and received a Ph.D. from the University of Illinois. He taught there and at Harvard before being hired by DuPont to head its program in basic science. Nylon was introduced to the public in 1939, but its widespread use was delayed until after World War II because all nylon produced during the war was used by the military. Carothers died unaware of the era of synthetic fibers that dawned after the war. 

Nylon was invented in 1935 by Wallace Carothers (1896-i937), an employee of the DuPont Chemical Corporation at the time. Carothers was searching for a synthetic substitute... 

Caprolactam was first synthesized in 1899 by Gabriel and Maas by heating e-aminocaproic acid. However, commercial interest in the material developed in 1937 when Dr. Paul Schlack of I. G. Farbenindustrie recognized that it could be used as a precursor for the polyamide, nylon 6. Nylon 6 is made from caprolactam, a six carbon molecule. Nylon 6/6 is made from adipic acid and hexamethylenediamine (HMDA), two six carbon molecules. Carothers of DuPont succeeded in producing nylon 6/6 in 1936 from adipic... 

---