Used primarily as a polymer additive, this compound functions as a heat stabilizer in polyvinyl chloride (PVC) and other chlorine-containing polymers. It helps prevent thermal degradation during processing and extends the service life of plastic products exposed to high temperatures. Its effectiveness is particularly notable in rigid PVC applications such as pipes, cables, and construction materials. Additionally, it acts as a synergist in flame retardant systems, enhancing the performance of other fire-inhibiting additives. Due to environmental and toxicity concerns, its use has declined in consumer products but remains in industrial applications where regulatory restrictions are less stringent.