Used primarily as a reactive intermediate in the synthesis of oil-soluble dispersants for lubricant additives. It reacts with polyamines to form dispersants that help keep engine deposits, sludge, and varnish in suspension, improving the performance and longevity of motor oils. Commonly employed in the formulation of internal combustion engine lubricants, especially in automotive and industrial applications. Its long hydrocarbon chain provides good oil solubility, while the anhydride group offers high reactivity for further chemical modification. Also utilized in the production of corrosion inhibitors and emulsifiers in fuel and lubricant systems.