高效凝胶渗透色谱法测定填料的孔分布

Determination of Pore Distribution of Column Packings by High Performance Gel Permeation Chro- matography

填料的平均孔径(MPDs)和孔分布(PSDs)特性参数十分重要,这些参数直接关系到色谱分析的物理化学过程。 通常用于测定孔径参数的压汞法和气体凝蒸法,设备昂贵而且对键合型担体的适应性较差。利用凝胶渗透色谱法(GPO)测定,方法简便,并可获悉分离过程的分子扩散特性。 本文选择了分子量(M)为800—50万的聚苯乙烯(PS)和M78—306的芳烃(AH)纯样为标样,利用标样的析出体积(Ve)和M值的关系曲线以及溶质的M和填料孔径(φ)的数学转换公式,建立了可以测定10A—1000A孔径分布方法。并以此测定了HSG—20,HSG-15等五种液相色谱填料。

This paper deals with the determination of the median pore diameters (MPDs) and pore size distributions (PSDs) of packings by high performance gel permeation chroma tography (GPC).In the GPC experiments, tne standards selected -ere the polystyrene (PS) with the molecular weight (M) ranged from 800 to 500000 and the aromatic hydrocarbon (AH) with the M ranged from 78 to 306. The measurement method of MPDs and PSDs was established bythe curve of logarithm of M vs. elution volumes of standards and a calculated formula ot transform M of solute into pore diameter of packing.The present method has been used to determine 5 packings of liquid phase chromatography. The results were tnat the MPDs of HSG-20, HSG-15, HSG-10. Zorbax-CN and Zorbax-NH2 were 39.2A. 22.7A 18.8A.42.9A and 120.3A respectively, and their PSDs ranges were about12-360A.