Adipic acid

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Adipic acid
Image:Adipic acid structure.png
General
Common name	adipic acid
Systematic name	hexanedioic acid
Other names	butane-1,4-dicarboxylic acid
Molecular formula	C₆H₁₀O₄
SMILES	OC(=O)CCCCC(=O)O
Molar mass	146.14 g/mol
Appearance	White crystals
CAS number	[124-04-9]
Properties
Density and phase	1.36 g/cm³
Solubility in water	slightly soluble
Other solvents ethanol, acetone	soluble
Melting point	153 °C (426 K)
Boiling point	337 °C (610 K)
Acidity	pK_a1=4.42 pK_a2=5.42
Structure
Molecular shape	?
Coordination geometry	?
Crystal structure	?
Dipole moment	? D
Hazards
MSDS	External MSDS
Main hazards	flammable
Flash point	232 °C
R/S statement	R: 36 S: n/a
RTECS number	?
Supplementary data page
Structure & properties	n, ε_r, etc.
Thermodynamic data	Phase behaviour Solid, liquid, gas
Spectral data	UV, IR, NMR, MS
Related compounds
Related dicarboxylic acids	glutaric acid pimelic acid
Related compounds	hexanoic acid
Except where noted otherwise, data are given for materials in their standard state (at 25°C, 100 kPa) Infobox disclaimer and references

Adipic acid (IUPAC systematic name: hexanedioic acid) is a chemical compound of the class of carboxylic acids. It is a white crystalline powder appearing as an acid in aqueous circumstances, though it is not highly soluble.

[edit] Preparation

Historically, adipic acid is prepared from various fats using oxidation. Current commercial adipic acid is produced from cyclohexane by two oxidation steps.

Cyclohexane + O₂ → cyclohexanol and cyclohexanone
cyclohexanol/cyclohexanone + nitric acid + air → adipic acid + nitrous oxide

[edit] Uses

By far the main use of adipic acid is as monomer for the production of nylon by a polycondensation reaction with hexamethylene diamine forming 6,6-nylon, the most common form of nylon. Other uses include:

° Monomer for production of Polyurethane

° reactant to form plasticizers and lubricant components

° Food Ingredient as a flavorant and gelling aid.E-number E355.

° FDA citations - GRAS (21 CFR 184.1009), Indirect additive (21 CFR 175.300, 21 CFR 175.320, 21 CFR 176.170, 21 CFR 176.180, 21 CFR 177.1200, 21 CFR 177.1390 , 21 CFR 177.1500 , 21 CFR 177.1630 , 21 CFR 177.1680, 21 CFR 177.2420, 21 CFR 177.2600)