Used as a crosslinking agent in polymer chemistry, particularly in the synthesis of porous organic frameworks and covalent organic frameworks (COFs). Its four reactive bromomethyl groups enable multi-directional coupling reactions, making it valuable for constructing 3D network structures. Commonly employed in step-growth polymerizations to build rigid, thermally stable materials for gas storage, catalysis, or molecular separation. Also utilized in the preparation of functional resins and dendritic macromolecules due to its high functionality and structural symmetry.