Caproic Caprolactam

Metabolism of NHEX- C in the rat results in dose dependent formation of C02> with 45% exhaled after a dose of 8 mg/kg NHEX but only 4% after 576 mg/kg (17). Similar results were obtained for NPYR and nitrosoheptamethyleneimine. At doses of 8-12 mg/kg NHEX, 33-37% of the radioactivity was excreted in the urine (17, 52). Urinary metabolites of NHEX were e-caprolactam, e-amino-caproic acid, and 6-aminocaprohydroxamic acid (52). The formation of 6-caprolactam is analogous to results with NPYR and NNN, in which 2-pyrrolidinone and norcotinine were observed as urinary metabolites. Caprolactam did not originate from hexamethylene-imine, a product of denitrosation. 

Calcium carbide, 32, 70 Calcium carbonate, 32, 81 Calcium formate, 31,102 CAPROIC ACID, e-AMINO, 32, 13 e-Caprolactam, 31, 72 32, 15 e-CAPROLACTIM, O-METHYL-, 31, 72 CAPRONITRILE, a-ETHYL, 32, 6S Caproyl chloride, 31, 71 CARBANILINONITRILE, O-CHLORO, 31, 19... 

Cadaverine, p30 2-Camphanone, c3 Capraldehyde, d7 Capric acid, dl5 Capric alcohol, dl6 Caproaldehyde, h51 Caproic acid, h64 Caproic anhydride, h65 6-(or e)-Caprolactam, 06I e-Caprolactone, h69... 

The common name caprolactam comes from the original name for the Ce carboxylic acid, caproic acid. Caprolactam is the cyclic amide (lactam) of 6-aminocaproic acid. Its manufacture is from cyclohexanone, made usually from cyclohexane (58%), but also available from phenol (42%). Some of the cyclohexanol in cyclohexanone/cyclohexanol mixtures can be converted to cyclohexanone by a ZnO catalyst at 400°C. Then the cyclohexanone is converted into the oxime with hydroxylamine. The oxime undergoes a very famous acid-catalyzed reaction called the Beckmann rearrangement to give caprolactam. Sulfuric acid at 100-120°C is common but phosphoric acid is also used, since after treatment with ammonia the by-product becomes... 

Hydrolytic polymerization of e-caprolactam to form nylon 6 (Sec. 2-8f) is carried out commercially in both batch and continuous processes by heating the monomer in the presence of 5-10% water to temperatures of 250-270°C for periods of 12 h to more than 24 h [Anton and Baird, 2002 Zimmerman, 1988]. Several equilibria are involved in the polymerization [Bertalan et al., 1984 Sekiguchi, 1984]. These are hydrolysis of the lactam to e-amino-caproic acid (Eq. 7-56), step polymerization of the amino acid with itself (Eq. 7-57), and initiation of ring-opening polymerization of lactam by the amino acid. The amino acid is... 

Capric acid, dl4 Caproaldehyde, h54 Caproic acid, h66 Caproic anhydride, h67 e-Caprolactam, o57 6-Caprolactone, h71 Capronitrile, h63 Caproyl chloride, h73 Caprylic acid, o29 Capryl alcohol, o30 Caprylaldehyde, o40... 

Caprolactam (melting point 69.3°C, density 1.02, flash point 125°C, fire point 140°C), so named because it is derived from the original name for the C6 carboxylic acid, caproic acid, is the cyclic amide (lactam) of 6-aminocaproic acid. 

As with glutamic acid production, some modification of the normal metabolic pathway of C. glutamicum imposed by the fermentation conditions, is necessary in order to accumulate lysine in the medium. At present, worldwide production of L-lysine by fermentation routes totals some 70,000 tonnes annually, about 40% of this by Japan. About 9,000 tonnes of racemic lysine (DL mixture) per year is also produced synthetically from petrochemical sources. One interesting synthetic substrate for DL-lysine is caprolactam (or 6-amino-caproic acid), a starting material, which is readily available on a tonnage scale from its use as a nylon monomer. 

The primary product of cyclohexanone oxidation is a-ketohydro-peroxide [130], subsequently converted to diketone, the semialdehyde of adipic acid [130,131], and adipic acid [130,131]. Valeric and caproic acids and caprolactam were detected among the oxidation products [130]. 

FIGURE 2.3 Comparison of observed and calculated concentration-time relationships for caprolactam (x), polymer chains (i ), and amino caproic acid (5i) fVo = 0.82 mol/kg, T = 259°C. Solid lines represent experimental data broken lines calculated using set-II parameters dotted lines calcnilated using set I parameters. (From Reimschuessel, H.K. and Nagasubramanian, K., Chem. Eng. ScL, 1972, 27, 1119. With permission.)... 

Nylon 6 1.14 o HiN-jCHils-lir-OH o)-amino-caproic acid / HN-CO caprolactam... 

Hexetidine 90] Hexetidine 99. See Hexetidine Hexoic acid. See Caproic acid Hexoic aldehyde. See Hexanal 1,6-Hexolactam. See Caprolactam Hexomax . Seeinvertase Hexone. See Methyl isobutyl ketone n-Hexoxyethoxyethanol. See Diethylene glycol n-hexyl ether Hexyl acetate... 

C14-18 alcohols C16-20 alcohols C7-9 alkyl benzyl phthalate Capric acid Caproic acid Caprolactam Caprylic acid Caprylic/capric triglyceride C12 dibasic acid Chlorinated alpha-olefin, liquid... 

Caprolactam for use as fibers is hydrolytically polymerized in batches as 80%-90% aqueous solutions with 0.2%-0.5% acetic acid and ethylene diamine at 250-280° C. The acetic acid acts as chain stabilizer (see above). The ethylene diamine increases the amine equivalent of PA 6 so that mixed weaves of Perlon and wool can be evenly dyed. The water is removed as steam in the polymerization progresses. Caprolactam is also polymerized continuously by what is known as the VK process (vereinfacht-A ontinuierliche, or simplified continuous, process). This process is carried out without pressure with, for example, 6-amino caproic acid or AH salt as initiator. In contrast to the production of nylon 6,6, this process can proceed continuously the melt can be directly spun from the reactor. Polyamide 6 fibers have good properties but they yellow slowly since pyrrole structures are formed at the chain ends. 

Ga. 2 N NaOH added during 40 min. at 2-4° to a suspension of N-benzoyl-a-chloro-f-caprolactam in methanol-water, stirred 1 hr. at 0-3°, treated with more base, and stirred an additional 3 hrs. at 0-3° -benzamido-a-chloro-caproic acid. Y 94.5%. R. Tull et al., J. Org. Ghem. 29, 2425 (1964). 

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