| Polyvinyl chloride (PVC) is an important one common plastics, as China's construction and development accelerated, PVC chemical building materials to be widely promoted, makes PVC industry to develop rapidly. However, the thermal stability of PVC processing worse during processing, Heat stabilizer must be added. Heat stabilizer including lead salts. Organic tin, thulium stabilizer and Ca/Zn stabilizers.In recent years, although lead salts and metal soap has been the main heat stabilizer system in China. But as the market demand for environmentally friendly materials are becoming more urgent. Non-toxic products for use in the field of heat stabilizer are still difficult to meet market demand. The prices of Organic tin is high, a simple calcium/zinc compounds also can not satisfy all the performance requirements. For calcium/zinc stabilizers composite application, its main focus in three aspects: thermal stability, coloring and the early "Zinc" burn.This paper conducted the following study:(1) Identify calcium/zinc soap, calcium/zinc ratio of the best elements;(2) Introduced new multi-functional groups anion to synthesis of calcium/zinc soap, and compare their thermal stability; most of the calcium/zinc heat stabilizer are metal salts of stearic acid. Synthesis of new calcium/zinc compounds: Introduced more anionic functional groups, such as the calcium phosphite, zinc phosphite.(3) Find new efficient auxiliary stabilizer; Find industrialized production of polyol modified substances such as esterification polyol, contain hydrophobic group -OCOR and hydrophilic group-OH.(4) Proposed assumptions of polyol thermal stability mechanism, Experiments were carried out to confirm the Mechanism of polyol thermal stability: As the catalyst of ZnCl2, Polyol and HCl can also react to play heat stabilizer role.
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