The Earlier Stage Study On Industrial Manufacture Of Ester-Tin Heat Stabilizer

Ester-tin is a kind of organo-tin heat stabilizer which has good properties, wide application, high effects and low poison. It's used as PVC heat stabilizer, and has a bright future. It's very important to simplify its manufacture process and reduce its manufacture cost, in order to realize the industralization of ester tin heat stabilizer, stimulate its use and development, and further more replace or reduce the use of heat stabilizer such as lead salt. In this article, the industrial process of ester-tin heat stabilizer bis-( β -methoxycarbonylethyl),bis-(isooctyl mercaptoacetate) tin and its intermediates isooctyl mercaptoacetate and bis( β -methoxy carbonylethyl) tin dichlorides are studied by means of orthogonal design.In this paper, a new process of isooctyl mercaptoacetate synthesis, which uses H-type big hole ion-exchange resin as catalyst, industrial mercaptoacetic acid and isooctyl alcohol as raw material is advanced. Many factors, which concerned with the reaction such as the proportion of raw materials, reaction temperature, reaction time and the quantity of the catalyst are studied. The optimistic process is determined and the main factor affecting the reaction is found. The properties and construction of this product are identified by refractive index and IR spectrum. In this process, the catalyst is high activity, easy to reclaim, and can be reused. The whole process is no pollution, high purity of product and high yield. It's both safe and clean.Bis-( β -methoxy carbonylethyl) tin dichlorides is the other important intermediate for ester-tin synthesis. A new process by means of mixing solvent, tin powder dry hydrogenchloride gas and methyl acrylate as raw materials is put forward. Manyfactors affecting reaction such as the ratio of mixing solvent, reaction temperature, reaction time and the ratio of raw materials are researched. The chief factor is found out and the optimistic process is determined. The properties and instruction of this intermediate are identified by IR spectrum, elementary analysis and tin content analysis. In this process, the synthesis is easy, the raw material is easy to obtain, high purity of the intermediate and the reaction can be carried out at ordinary temperature and pressure.In addition, ester-tin stabilizer is prepared by reacting of bis-( (3 -methoxy carbonylethyl) tin dichlorides and isooctyl mercaptoacetate. The study on the proportion of two intermediates is carried out. Synthronally, the optimistic scheme is determined. The contruction of this product is identified by IR spectrum. The heat stability is tested according to national standard GB2917-82, and the satisfy result is obtained.This stabilizer has high purity, excellent heat stability. The process is easy, The material is easy to obtain, the equipments are universal machines, and no harmful by-products produced. So it is a practically useful process.