The function and application of adipic acid

The role and use of adipic acid
Adipic acid is often used as a key raw material for the synthesis of polyester polyols in the field of polyurethane synthesis. Polyester polyols with different chain lengths and properties can be prepared by condensation reaction with diols. For example, when preparing soft polyurethane foam, the polymer chain segment formed with adipic acid in the polyester polyol used gives the foam good flexibility and resilience, and its amount is generally 30% -50% of the total mass of the formula raw materials.
Adipic acid is one of the important monomers for producing nylon 66. During the synthesis of nylon 66, adipic acid undergoes a condensation reaction with hexamethylenediamine. Accurate control of reaction conditions, such as reaction temperature between 220-280 ℃ and pressure between 1.5-3MPa, can enhance the strength and wear resistance of nylon 66, which is widely used in industries such as textiles and automotive parts. In the field of lubricant additives, adipic acid can be used to synthesize additives with specific structures. For example, by reacting with specific amine compounds, the products can improve the antioxidant and anti-wear properties of lubricating oil. In some high-performance engine lubricating oils, the amount of such additives added is about 0.5% to 2%, effectively extending the service life of the lubricating oil and the operating time of the equipment. Adipic acid plays a role in the preparation of plastic plasticizers. A series of adipic acid ester plasticizers can be obtained by esterification reaction with alcohol substances. Like dioctyl adipate (DOA), it has good cold resistance and plasticizing effect. In the processing of polyvinyl chloride (PVC) plastics, the addition amount is usually between 5% and 15%, which can effectively improve the processing performance of PVC and the flexibility of products. As a food additive, adipic acid has specific uses in the food industry. It can be used as an acidity regulator to adjust the acidity and alkalinity of food. In some jam and jelly products, adding a moderate amount of adipic acid (usually 0.1% -0.5%) can improve the flavor and stability of the product, prevent microbial growth, and adjust the acidity of the taste, making it more refreshing and delicious.

In the pharmaceutical industry, adipic acid can be used to synthesize certain pharmaceutical intermediates. For example, in the synthesis of some cardiovascular disease treatment drugs, adipic acid participates in specific reaction steps and constructs key structural parts of drug molecules through specific chemical reaction pathways, providing a foundation for the subsequent synthesis of drugs. Adipic acid can be used to manufacture biodegradable materials. By blending with natural polymer materials such as starch and cellulose or through chemical modification, the physical and processing properties of the material can be improved, making it easier to shape and process. In the field of environmentally friendly packaging materials, these biodegradable materials are expected to gradually replace traditional non biodegradable plastic products. In the coatings industry, adipic acid can be used to synthesize polyester resin coatings. It is a polyester resin that reacts with raw materials such as polyols and polyacids, and has good water resistance, weather resistance, and glossiness. In some industrial coating formulations, polyester resin synthesized from adipic acid accounts for 40% -60% of the total coating mass, which can provide good protection and decorative performance for the coated object. Adipic acid is also used in the leather industry. It can be used as an auxiliary tanning agent in the leather tanning process. Through certain chemical reaction with collagen in leather, it helps to improve the softness and fullness of leather, enhance the water resistance and anti-aging performance of leather, and improve the quality of leather products.
In the electronics and electrical industry, adipic acid is involved in the synthesis of some high-performance engineering plastics. For example, in engineering plastics used to manufacture electronic device casings, polymers containing adipic acid structural units can improve the flame retardancy, mechanical strength, and dimensional stability of plastics. In some high-end electronic device casing materials, the application proportion of such engineering plastics is gradually increasing to meet the strict performance requirements of products.