恒电流库仑分析法测定乙烯基三乙氧基硅烷

Determination of vinyltriethoxysilane by constant-current coulometric analysis

建立了恒电流库仑分析法测定乙烯基三乙氧基硅烷（VTES）含量的方法。探讨了电解液、反应时间、极化电位、溶剂等因素对测定的影响。结果表明，选用V（甲酸）：V（KBr（2 mol／L））：V（乙醇）=6：1：3为电解液，极化电位为200mV，VTES与溴的四氯化碳溶液反应30min，甲醇为、VTES的溶剂时测定结果最佳。该方法用于样品VTES的测定，加标回收率为98．4％～102．7％，相对标准偏差为1．7％。

A constant-current coulometric analysis method has been established to determine the content of vinyltriethoxysilane （VTES） sample quantitatively, based on the quantitative reaction between WFES and neonatal bromine and the reaction of As（ Ⅲ ） with the surplus bromine. The optimal conditions such as electrolyte, reaction time and polarization potential etc were investigated with respect to their effects on the results systematically. It was found that the best results were obtained under the following conditions： formic acid： potassium bromide （2 mol/L） ： ethanol = 6：1：3 （volume ratio） as the electrolyte, reaction time at 30 min, polarization potential at 200 mV and methanol as the solvent. This method has been applied to the determination of the content of a Shuguang VTES sample, the recoveries of standard addition were found between 98.4% and 102.7%, with the relative standard deviation was 1.7%.