Nylon commercial production stockings

There is very httle information available on the commercial production of pure cycloparaffins. Although feed stocks composed of this class of hydrocarbons are used in the manufacture of aromatics, chemical-grade cycloparaffins ha ve not been produced extensively. Highly purified cyclohexane is being used in production of nylon. References to the cycloparaffins are listed under Miscellaneous. 

Nylon 66 was first made in 1935 and went into commercial production in 1940. Its fibers were strong, elastic, abrasion resistant, lustrous, and easy to wash. With these qualities, nylon became more than just a good substitute for silk in stockings. Today it is used in a multitude of products, including carpeting, upholstery fabrics, automobile tires, and turf for athletic fields. 

Nylon, not publicly announced until 1938, was first used for bristles on combs, but made headlines in 1939 when nylon stockings debuted at the World s Fair in New York City. Nylon is known by its chemical name, poly(hexamethylene) adipamide, but more often simply as nylon. The first nylon manufecturing plant went into production at Seaford, Delaware, in 1940. Commercial production of nylon 6 by IG Earben in Germany began in 1941. These two plants would go on to produce millions of pounds of nylon annually. This mass production was essential to the World War II effort, as nylon was used for everything from belts, ropes, and straps to tents and parachutes. 

As mentioned in Chapter 1, the commercial development of nylons was an outcome of the fundamental researches into polymerization which were begun in 1929 by Carothers of E.I. du Pont de Nemours and Co. Several polyamides and polyesters were investigated nylon 6,6 (see later for nomenclature) was first synthesized in 1935 and was selected as the most promising fibre-forming material. Commercial production was started in 1938 nylon stockings were put on trial sale in 1939 and became generally available in the UJS.A. in 1940. The... 

Nylon finally became available to the general public in May 1940. Ten years had passed from initial discovery to full commercialization. It was a tremendous effort, even for a company with the resources of DuPont, and the R D cost was 4.3 million. During World War II, DuPont nylon production went up to 25 million pounds a year, and was used to make parachutes, airplane tire cords, and glider tow ropes. DuPont resumed selling nylon for stockings after the war. 

Even yet experts say that the best combs are saw-cut from flat uniform pieces of bone (and such combs remain on sale in more-expensive shops). Combs can be cut in the same way from plastic sheet, achieving comparable quality, but the stock must be prepared suitably and the work as a whole is more costly than the commercial method of making plastic combs in large numbers—injection moulding using materials such as nylon or polypropylene from the moulding process, after removal of the sprues, fully finished, saleable products (teeth included) can be obtained in a few seconds. 

Data in this report are generated from both commercial and developmental flat-sheet CA membranes. CA manbranes are prepared by dissolving commercial grades of CA polymers into a solvenl/non-solvent mixture to give a highly viscous dope solution. After microfiltration a knife blade is used to spread the dope onto a woven nylon substrate. The commercial equipment utilized allows for a 1-m width to be cast. The thin dope film is quenched into a water bath to form the microporous structure by the phase inversion process. Membrane is washed with water and post-treated to give finished product in dry state as roll stock. 

Several other common thermoplastics emerged about the same time as LDPE in 1930s. Polystyrene, for instance, was first produced in 1930 and by 1934 plants were in operation producing the commercial resin in both Germany and Ihe United States. Poly(methyhnethacrylate) (PMMA) was developed by ICI about the same period. Carothers s discovery of nylons (introduced in 1939 at the World s Fair in New York) yielded a material that particularly served the allied war effort. Nylon was used extensively in tire reinforcement, parachute fabric, as well as in everyday products such as toothbrushes and women s stockings. Engineering thermoplastics such as polycarbonate by comparison are a more recent development, with commercialization by General Electric Company around 1958. 

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