Used primarily as a reactive intermediate in organic synthesis, especially in the production of high-performance resins and polymers. Its anhydride functionality allows it to participate in cross-linking reactions, making it valuable in epoxy curing agents where it contributes to thermal stability and mechanical strength. Commonly found in coatings, adhesives, and composite materials requiring durability and resistance to heat and chemicals. Also utilized in the synthesis of specialty chemicals and plasticizers due to its cyclic structure and functional reactivity.