The main reason for adding PVC thermal stabilizer in plastic formulation design is that it can capture the HCL released by PVC resin with self-catalytic action,and can react with the unstable polyene structure produced by PVC resin to prevent or reduce the decomposition of PVC resin.In order to better solve the PVC processing may appear in a variety of adverse phenomena.
　　The PVC heat stabilizer selected in the general formula needs to be considered according to its own characteristics,functions and product requirements.For example,the lead salt compound stabilizer mainly used in hard products has the characteristics of good thermal stabilizer,excellent electrical performance,low price and so on.The disadvantage is more toxic,easy to pollute products,can only produce opaque products.
　　Calcium zinc compound stabilizer can be used as environmental stabilizer in food packaging,medical equipment and medicine packaging,but its stability is relatively low,the amount of calcium stabilizer is poor transparency,easy to spray cream.Calcium zinc composite stabilizer generally uses polyols and antioxidants to improve its performance.Recently,calcium zinc composite stabilizer has been used for hard pipes in the industry.
　　The above two categories are currently more commonly used PVC thermal stabilizer,but the actual application is not limited to this,also includes organotin thermal stabilizer,epoxy stabilizer,rare earth stabilizer and hydrotalc stabilizer.