PVC with a metal soap stabilizers which

Metal soap as a stabilizer , mainly for the plastics industry , particularly PVC use more. Stabilizers for PVC , mostly cadmium, barium, calcium, zinc , aluminum, magnesium salts of higher fatty Diethylene glycol dibenzoate  acids , especially stearic acid and lauric acid salts. They play the role of hydrogen chloride acceptor , a carboxyl group and a metal soap PVC replacement reaction of the chlorine atoms , the esterification of PVC stabilized. In most cases, the esterification reaction rate ZnCdPdCaBa. Because cadmium toxicity, have now banned . Zinc soap is best complementary stabilizer, but long-term stability is poor , the price cheaper , non-toxic , can be used in food packaging films . Common Ownership zinc stearate , zinc laurate , ... PVC heat stabilizers generally based on processing tribasic lead sulfate ( three salt ) , dibasic lead stearate ( two salt ) -based, then add  aluminum hydroxide a small amount of lead stearate ( hard lead ) and calcium stearate ( hard calcium ) , may be used alone , can be reasonable, made ​​of composite lead salt stabilizer. The toxicity of lead cause for great concern , three salt , two lead salt stabilizer higher indifferent people , and thus the metal soap -based heat stabilizer ( particularly a lead-free metal soap ) for people concerned , the thermal stability of the metal soap mechanism has become a hot topic. Because PVC heat stabilizers in the production aspect is protected by patents , so there is no reported its exact composition and potassium soap  content . Commercial heat stabilizers are commercially available mixture of various compounds . Mixture is better than pure substances stabilizing effect . Meanwhile , in dealing PVC heat stabilizers are required to carefully consider its toxicity. PVC, processors and consumers should pay attention to warnings about the toxicity of stabilizer .