本文用聚乙二醇（M=4000、6000、10000、20000）为标准物质，用分光光度法研究了不同分子量聚乙二醇的最大吸收波长，考察了显色剂用量、显色时间等因素对聚乙二醇溶液吸光度的影响，对方法的最佳测定条件进行选择。该法简便、快速、有较高的精密度，可用于聚丙烯腈共混超滤膜的截留率和透水率的浏定。

Several kinds of Polyethylene glycol with different molecular weight (M=4000、6000、1000、20000) are used as the standard substances in the investigation their maximum absorption bands by ultraviolet spectrophotometry. The influences of some factors, including chromogenic reagent dosage, chromogenic reaction time and so on, are also investigated. The optimal amount of iodine, amount of BaCl2 and chromogenic reaction tim are 0.1 mL, 2.0 mL and 420~660 s, respectively. This method is simple, fast and has high accuracy. It is suitable for the determination of rejection rate and water flux of PSF/PAN blend ultrafiltration membrane.

广东省科技公关项目(2004B10201001)；广州市科技成果推广项目（2006C13G0011）