Used as a stabilizer in polymers, particularly in polyvinyl chloride (PVC), to improve thermal stability during processing. Acts as an effective antioxidant by scavenging free radicals and preventing degradation. Employed in the synthesis of organophosphorus compounds for use in flame retardants and plasticizers. Also serves as a ligand or intermediate in organic synthesis and catalysis, especially in transition metal-catalyzed reactions. Its reactivity makes it valuable in the production of specialty chemicals and crosslinking agents for resins and coatings.