新型聚氯乙烯热稳定剂双巯基乙酸异辛酯二正辛基锡的合成

SYNTHESIS OF DI-n-OCTYLTIN BIS(ISOCTYL THIOGLYCOLLATE)AS THERMAL STABILIZER FOR POLYVINYL CHLORIDE

实验以二正辛基氧化锡和巯基乙酸异辛酯为原料,合成了辛基锡类聚氯乙烯高效热稳定剂——双巯基乙酸异辛酯二正辛基锡。选择溴辛烷法,在季铵盐和碘的协同催化下,溴代正辛烷与锡粉反应生成二正辛基二溴化锡,再经水解得到二正辛基氧化锡,收率达83.1%。巯基乙酸异辛酯的制备采用先酯化后巯基化法,在氯乙酸与异辛醇的酯化反应中,以固载无机盐为催化剂;巯基化过程采用Bunte盐法,产物收率为91.5%,纯度为98.5%。

To synthesize the thermal stabilizer of di-n-octyltin bis（isoctyl thioglycollate）, di n-octyltin oxide and isooctyl mercaptoacetate were used as reactants. Considering the production cost and reaction activity, bromide method was chosen to synthesize di-n octyltin, that is, n octylbromide and tin reacted with the effect of catalyst with the yield of di-n-octyltin oxide 83.1%. To synthesize isooctyl mercaptoacetate, chloroacetate and isooctanol were used as reactants which were catalyzed by supported inorganic salts. Then Bunte Salts was hydrolyzed in acid medium, and finally isooctyl mercaptoac-etatewas formed. The yield was 91.5%, and the purity was 98.5%. Di-n-octyltinoxideandisooctyl mercaptoacetate reacted in negative pressure, and the thermal stabilizer of din octyltin bis（isoetyl thioglycollate） was formed. The influences of reaction time and temperature were examined.