Used as a building block in the synthesis of high-performance polymers and resins due to its rigid cyclic structure and multiple functional groups. Its four carboxylic acid groups allow for cross-linking in polyimides and polyesters, enhancing thermal stability and mechanical strength. Commonly applied in heat-resistant coatings, electronic materials, and advanced composites. Also explored in metal-organic frameworks (MOFs) for gas storage or catalysis owing to its ability to chelate metal ions.