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Thioglycolic acid methyl tin isooctyl most prominent varieties of PVC heat stabilizers performance , widely used in PVC synthetic products and related products in the preparation process . Its preparation and application , a lot of research work , while the conventional synthetic methods there is a complex process , high production costs , and cause serious environmental pollution . Synthesis of isooctyl thioglycolic acid methyl tin for the inadequacies of the current process , the intrinsic reaction mechanism, low voltage step synthesis of methyl tin thioglycolic acid isooctyl , and synthesis process parameters are optimized , the specific work as follows : first, the traditional synthesis route improvements, eliminating the need for intermediate purification operation in the two-step method , the design intermediates absorbing device , easy to operate , so the cost is greatly reduced . Second, the conventional synthetic intermediates catalyst analysis screening trials comparing selected trimethylamine hydrochloride as a synthetic intermediate methyl chloride tin catalyst , having a mild reaction conditions , and product yield , inexpensive advantages. Third, the process of synthesis intermediates methyl tin chloride optimized results show that at 200 ° C for 1 to 2 MPa , the reaction time of 8 hours, the catalyst is used in an amount of tinfoil input amount of 3.5% under the conditions , intermediate A base tin chloride yield more than 83% . Fourth, in the the synthetic intermediates methyl chloride, tin crude premise homemade absorbing means , directly to the methyl chloride, tin crude product absorbed into the solvent mercapto acetic acid , isooctyl , and the synthesis of methyl tin mercapto Isooctyl the ester process conditions optimization , the results showed that: isooctyl methyl tin chloride : thioglycolic acid = 1:2 (wt%), reaction temperature 40 ° C , reaction time 1h, sodium carbonate added speed : the first 30 minutes 30g / h, to 10g / h under the conditions of the product yield rate of 83.7% after 30 minutes . Fifth, by high performance liquid chromatography, atomic emission spectroscopy and other analytical instruments , prepared thioglycolic acid methyl tin isooctyl acrylate were analyzed, the results showed that the samples prepared reached sheet pipe technical indicators . Sixth , prepared methyl tin sulfhydryl Isooctyl the practical application of the experimental results showed that : rather, to meet the requirements of products for industrial applications with the commercial performance of similar products .
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