Caprolactam, for nylon

Adipic acid is a very large volume organic chemical. Worldwide production in 1986 reached 1.6 x 10 t (3.5 x 10 lb) (158) and in 1989 was estimated at more than 1.9 x 10 t (Table 7). It is one of the top fifty (159) chemicals produced in the United States in terms of volume, with 1989 production estimated at 745,000 t (160). Growth rate in demand in the United States for the period 1988—1993 is estimated at 2.5% per year based on 1987—1989 (160). Table 7 provides individual capacities for U.S. manufacturers. Western European capacity is essentially equivalent to that in the United States at 800,000 t/yr. Demand is highly cycHc (161), reflecting the automotive and housing markets especially. Prices usually foUow the variabiUty in cmde oil prices. Adipic acid for nylon takes about 60% of U.S. cyclohexane production the remainder goes to caprolactam for nylon-6, export, and miscellaneous uses (162). In 1989 about 88% of U.S. adipic acid production was used in nylon-6,6 (77% fiber and 11% resin), 3% in polyurethanes, 2.5% in plasticizers, 2.7% miscellaneous, and 4.5% exported (160). 

Ketones are an important class of industrial chemicals that have found widespread use as solvents and chemical intermediates. Acetone (qv) is the simplest and most important ketone and finds ubiquitous use as a solvent. Higher members of the aUphatic methyl ketone series (eg, methyl ethyl ketone, methyl isobutyl ketone, and methyl amyl ketone) are also industrially significant solvents. Cyclohexanone is the most important cycHc ketone and is primarily used in the manufacture of y-caprolactam for nylon-6 (see Cyclohexanoland cyclohexanone). Other ketones find appHcation in fields as diverse as fragrance formulation and metals extraction. Although the industrially important ketones are reviewed herein, the laboratory preparation of ketones is covered elsewhere (1). 

The most important use of cyclohexanone is as a chemical intermediate in nylon manufacture 97% of all cyclohexanone output is used either to make caprolactam for nylon-6, or adipic acid for nylon-6,6. In the caprolactam process cyclohexanone is converted to cyclohexanone oxime (mp,... 

Particular reactions can occur in either or both phases or near the interface. Nitration of aromatics with HNO3-H2SO4 occurs in the aqueous phase (Albright and Hanson, eds.. Industrial and Laboratoiy Nitration.s, ACS Symposium Series 22 [1975]). An industrial example of reaction in both phases is the oximation of cyclohexanone, a step in the manufacture of caprolactam for nylon (Rod, Proc. 4th Interna-tional/6th European Symposium on Chemical Reactions, Heidelberg, Pergamon, 1976, p. 275). The reaction between butene and isobutane... 

Adipic acid is a very large-volume organic chemical. It is one of the top 50 chemicals produced in the United States in terms of volume. Demand is highly cyclic, reflecting the automotive and housing markets especially. Prices usually follow the variability in crude oil prices. Adipic acid for nylon takes about 60% of U.S. cyclohexane production the remainder goes to caprolactam for nylon-6, export, and miscellaneous uses. 

The number of fragment molecules obtained during pyrolysis of nylon 12 is higher than that for nylon 6. However, the similarity in the reaction types occurring during pyrolysis of the two polymers is obvious. Even formation of azacyclotridecan-2-one, which is the equivalent of caprolactam for nylon 6, takes place in the pyrolytic process of nylon 12. 

The significance of the reaction of phenol with hydrogen has a number of important facets. First, the selective hydrogenation of phenol yields cyclohexanone, which is a key raw material in the production of both caprolactam for nylon 6 and adipic acid for nylon 6 . Second, due to the fact that phenol is an environmental toxin and phenolic waste has a variety of origins from industrial sources including oil refineries, petrochemical units, polymeric resin manufacturing and plastic units , catalytic hydrogenation of phenol is nowadays the best practicable environmental option . ... 

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. 

Cyclohexanone - hek-so- non (ca. 1909) (pimelic ketone, ketohexamethylene) n. CH2(CH2)4C=0. a colorless liquid produced by the oxidation of cyclohexane or cyclohexanol. Its most important use is for the manufacturer of adipic acid for nylon 6/6, and caprolactam for nylon 6. It is also an excellent high-boiling, slowly evaporating solvent for many resins including cellulosics, acrylics and vinyls. It is one of the most powerful solvents for PVC, and is often used in lacquers to improve their adhesion to PVC (See image). 

About 60% of cyclohexane production is used to make adipic acid and hexamethyl-ene diamine for nylon-6,6 production, as well as the caprolactam for nylon-6 production. About 70% of all caprolactam is produced from cyclohexane (mainly used to synthesize nylon-6). 

Ans TerephthaUc acid and ethylene glycol (or dimethyl terephthalate) for PET, cyclohexanone oxime or caprolactam for nylon 6, adipic acid and hexamethylene diamine for nylon 6,6, and lactide for polylactide, respectively. (a) Unlike PET, polylactide is a biodegradable material (b) nitrous oxide is a greenhouse gas and an ozone depleter, and as it cannot be recycled, its removal is essential (c) conventional bleaching produces... 

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