Study On The Synthesis And Stability Mechanism Of Organic Antimony As New Thermal Stabilizer For PVC

PVC is a kind of polymer materials applied widely. But its development is restricted because of its disadvantages, such as poor thermal stability, combustible property and so on. Thus,the study on PVC heat stabilizer become one of key problems in this research. The traditional PVC heat stabilizer including the lead salt and cadmium salt stabilizer, is harmful to human health and environment. Therefor, it is a difficult problem faced by PVC industry to develop a new, high efficient, low-toxic or no-toxic heat stabilizer.Antimony organic heat stabilizer is a low toxicity and the efficient heat stabilizers. In 1978, the World Health Organization approved organic antimony can be used on rigid PVC pipes. It has been reported: acute oral toxicity of antimony mercaptide volume (rats) for the 1600 ~ 2800mg/kg, and tin mercaptan 700 ~ 2000mg/kg. Secondly, antimony deposit abundant in china, to expand the scope of the antimony element is also in line with China's national conditions, the environment and a lot of economic interests.The organic antimony stabilizer is a important heat stabilizer with high efficiency and low toxicity. In this paper, antimony pent (cinnamyl thiolycollate) as a new type of the organic antimony stabilizer was synthesized. The optimal synthesis process is as follows: the molar ratio of reactants was 1/13, solvent volume was 70mL, reaction time was 3h, pH was 7, yeild of the product was 92%, the antimony content was 10.32%. Antimony pent (cinnamyl thiolycollate) was identified by IR. The thermal stability of Antimony pent (cinnamyl thiolycollate) was evaluated by static and dynamic method, the results indicated that it had good thermal stability. The synergistic effect of antimony pent (cinnamyl thiolycollate) and the other heat stabilizers was studied. The results showed that it is a good synergistic effect between antimony pent (cinnamyl thiolycollate) and the traditional heat stabilizers. The stability mechanism was conferred by IR, which was as follows: Sb is dsp3 hybridization, the electronic space configuration is the trigonal bipyramidal type, the formation of was prevented by the coordination of antimony and chlorine atoms, the stability was enhanced by the sulfhydryl substituting the chlorine atoms.