by Hexanedioic acid is produced on an industrial scale through a multistep chemical process. The process starts with the oxidation of cyclohexanol or cyclohexane to produce cyclohexanone and cyclohexanol. These products then undergo a nitric acid oxidation reaction to form hexanedioic acid.
The overall chemical reaction can be summarized as:
C6H12 + O2 → C6H10O + H2O
C6H10O + HNO3 → C6H10(COOH)2 + HNO2 + H2O
This leads to the formation of hexanedioic acid (C6H10(COOH)2), which crystallizes out of the reaction mixture. The hexanedioic acid crystals are then separated by filtration. Some side products like glutaric acid may also form in small amounts.
The chemical possesses two carboxyl functional groups attached to a six-carbon aliphatic chain. It is a white, odorless, crystalline solid at room temperature. Hexanedioic acid is soluble in water, alcohol, and ether due to the polarity imparted by the carboxyl groups. Its melting point is around 152°C.
Uses of Adipic Acid in Manufacturing Nylon Compounds
One of the largest applications of Adipic Acid is in the production of nylon 6,6. In this process, hexanedioic acid reacts with hexamethylenediamine to form the repeat unit of nylon polymer.
The reaction involves the condensation of hexanedioic acid and hexamethylenediamine under heated conditions. The carboxylic acid groups in hexanedioic acid combine with the amine groups in hexamethylenediamine to form amide links. This leads to the formation of long chains of nylon polymer.
C6H10(COOH)2 + H2N(CH2)6NH2 → (-CO(CH2)4CO-)n + 2H2O
Nylon 6,6 is widely used to produce textiles, carpets, clothing, parachutes, ropes, medical sutures and more. It provides excellent strength, elasticity, durability and resistance to abrasion. Hexanedioic acid serves as an important building block in the mass production of this commercially important polyamide.
Uses in Plastics, Coatings and Food Additives
In addition to nylon, hexanedioic acid finds various other applications as well. It is used in the manufacture of plasticizers, which are additives meant to increase the flexibility, workability or distensibility of materials like plastics, concrete, mortar, etc. Hexanedioic acid acts as an intermediate in producing plasticizers like diethyl adipate, dioctyl adipate and others.
The chemical sees substantial consumption in polyurethane coatings and paints industry too. It enters into the production of alkyd and polyester resins involved in manufacturing paints and surface coatings. Some of the resulting polyester resins find usage as powder coatings for industrial metal finishing.
Adipic Acid is approved by the U.S. Food and Drug Administration for use as a food additive. It has the E number E354 and can be added to foods as an acidity regulator, pH buffer and preservative. Confectioneries, baked products and meat products may contain hexanedioic acid in trace amounts.
Other Minor Applications
A few other minor applications of hexanedioic acid include use in manufacturing synthetic lubricants, food flavorings and fragrances. It is also utilized as a starting material in producing chemicals like hexamethylenediamine, nylon 6 and caprolactam. Hexanedioic acid further sees limited applications as a corrosion inhibitor in certain industries. Pharmaceutical industry uses it in preparations of some drug formulations as well.
Adipic Acid is a commodity chemical produced on a large scale for diverse industrialneeds. Key among its uses is the production of nylon 6,6 for textiles and fibers. The material also adds value in plastics, coatings, food ingredients and other minor applications. With demand rising steadily over the years from major end-use segments, hexanedioic acid continues to be an important product in bulk chemical manufacturing.
*Note:
1. Source: Coherent Market Insights, Public sources, Desk research
2. We have leveraged AI tools to mine information and compile it
About Author - Vaagisha Singh
Vaagisha brings over three years of expertise as a content editor in the market research domain. Originally a creative writer, she discovered her passion for editing, combining her flair for writing with a meticulous eye for detail. Her ability to craft and refine compelling content makes her an invaluable asset in delivering polished and engaging write-ups. LinkedIn
