High-Purity Adipic Acid and
N2O Abatement Technology Licensing

Nylon, a class of aliphatic polyamides, is the single largest commercial application for Adi-pure high-purity adipic acid. Nylon 66 and nylon 6 are the most economically important nylons. Both can be converted to fibers, used for carpets, apparel, tire cord and industrial applications, or to engineering resins, used for automotive parts, electrical and electronic applications, machine parts, films, wire coatings and monofilament.
 

Polyurethanes (PUs) are among the most versatile plastics available today, offering different properties suitable for many end uses. PUs are available in several forms, each with different potential applications. Most PUs are produced from the reaction of either a polyester or polyether polyol with a diisocyanate and chain extender to give a variety of physical and chemical properties.
 

A plasticizer is a substance which when added to a material (usually a plastic), makes it flexible, resilient and easier to handle. Modern plasticizers are man-made organic chemicals, the majority of which are diesters produced from high-molecular-weight alcohols such as adipic and phthalic acid.
 

An excipient is an inert or inactive substance that is used in tablets as a filler, binder, lubricant or disintegrant. Adi-pure adipic acid from INVISTA is ideally suited for use as an excipient in tablet manufacture, as it can play a number of roles in the tablet.
 

Adipic acid is used extensively in the manufacture of polyamide-epichlorohydrin wet-strength resins. Similar products can also be manufactured using dimethyl adipate or other adipate esters.
 

Unsaturated polyester resins are the third-largest class of thermoset molding resins. These polyesters are low-molecular-weight viscous liquids dissolved in vinyl monomers like styrene to facilitate molding or shaping of the resin into a desired form before curing to rigid solids. Adi-pure adipic acid improves tensile and flexural strength in these resins and, at high levels, can give soft, pliable products for specialty applications.
 

Synthetic lubricants are man-made formulations of chemicals that increase the performance and productivity of machinery. Most synthetic lubricants are made from polyalphaolefin or ester-based fluids and an additive package. The proportion of base fluid can be up to 75% of the formulation. Because synthetic lubricants are composed of structurally uniform molecules with well-defined properties, they offer advantages over conventional oil and greases.
 

Adi-pure® adipic acid can be used for the synthesis of a range of chemical intermediates, include adiponitrile, the key intermediate for manufacturing of 1,6-hexanediamine; cyclopentanone, an intermediate used in the synthesis of flavour and fragrance chemicals, glutaric acid and biologically active compounds; 1,6-hexanediol, a valuable chemical intermediate used in polyester polyol, urethane and alkyd resin manufacture; and dimethyl sebacate, from which sebacic acid can be easily prepared.
 

Sequestrants are employed in a diverse range of products and processes – from household products to industrial applications. Sequestrants are used to sequester metal ions such as iron, copper, nickel, cobalt, chromium, calcium and manganese by forming strongly associated but soluble complexes with metal ions. These metal ions find their way into products as a result of, for example, hardness in water, directly from the soil or as a contaminant in raw materials.
 

Solder flux and flux-cored solders are used to improve the quality of electrical connections by cleaning connector surfaces and promoting metal-to-metal bonding. Adipic acid is used in a number of flux and flux-cored solder formulations to activate the flux, promote metal cleaning and minimize residual impurities and corrosion. The very low trace impurity levels of Adi-pure® high-purity adipic acid make it highly desirable for high-quality electronics applications.
 

Carboxy-terminated polyesters are often used as curing agents for glycidyl ether resins and for epoxidized olefin resins. The carboxy-terminated polyester prepared from adipic acid, diethylene glycol and glycerol is used as a curing agent for the diglycidyl ether of bisphenol A. Adipic acid and similar saturated dibasic acids are used with diepoxy resins to promote etherification or are used in substantial excess with a suitable catalyst to accomplish resin cross-linking by condensation esterification.
 

The primary function of a tanning agent is to stabilize collagen fibers in the fresh hide so they are not readily biodegradable. Adipic acid can be used to improve leather quality and to increase the utilization of chromium salts in tanning liquors, thereby minimizing chromium losses to effluent streams.
 

Adipic acid and mixed dibasic acids that contain adipic acid are routinely used to enhance the performance of wet limestone scrubbers for flue gas desulfurization. Adipic acid acts as a buffer, improves the scrubber efficiency by increasing the dissolution rate of limestone into the liquid slurry fed to the scrubber, and improves the mass transfer of sulfur dioxide from the gas phase to the scrubber liquid.
 

Adipic acid and its derivatives can be used in a variety of cleaning applications, ranging from laundry detergents and bleaches to dishwashing detergents and hard-surface cleaners. Laundry detergents that contain adipic acid form water-soluble salts or chelate complexes and prevent redeposition of calcium, magnesium and other metal salts onto fabrics. The chelating properties of adipic acid are also valuable in formulating dish-washing detergents and hard-surface cleaners for use in bathrooms and kitchens.