自动电位滴定法测定PTMEG羟基值及误差消除

Determining Hydroxyl Number of PTMEG by Automatic Potentiometric Titration Method and Eliminating Deviation

开发一种全自动电位滴定法测定聚四亚甲基醚二醇中羟基值及分子量大小,仪器由一台万通905自动电位滴定仪和四台自动配液单元组成,以氢氧化四丁铵标准溶液为滴定剂,采用过量返滴定方式大大缩短检测时间,通过控制溶剂水分、温度校正、空白值控制和溶液配制等有效消除误差,测定结果偏差控制在±2. 5‰范围内,满足工业化生产控制和产品出厂质量控制的需要。

An automatic potentionmetric titration method was developed to determine the hydtoxyl number content and molecular weight of PTMEG, The equipment was composed of one Metrohm 905 titrator, and four dosing devices, with the hydroxide tetrabutylammonium standard titration solution as the titrant, to shorten the testing time by the excessive titration method, eliminate deviation by controlling the water content of solvents, blank value, solution preparation and temperature correction, and ensure the determining deviation in ±2.5‰. It met the needs of the quality controlling in industrial production.