Valorization of palm oil refining by-product for organotin mercaptide as a polyvinyl chloride thermal stabilizer: Synthesis, efficacy and comparison to mixed metal stearate

Abstract

Organotin mercaptide-based thermal stabilizer is recognized for its effectiveness in enhancing thermal stability of polyvinyl chloride (PVC). In this study, we synthesized an organotin mercaptide-based thermal stabilizer from palm fatty acid distillate, which is a by-product of palm oil refining process, and then evaluated its thermal stabilizing effects on PVC and compared its efficacy and economics to those of mixed metal stearate. The synthesized thermal stabilizer manifests as methyltin mercaptoethyl carboxylate sulfides. Both dehydrochlorination and two-roll mill discoloration tests have demonstrated the high efficacy of the resulting thermal stabilizer in stabilizing PVC, surpassing the performance of mixed metal stearate, as evidenced by the lower dosage required. The synthesized PVC thermal stabilizer not only provides effective stabilization but also presents a competitive viable alternative.