体积排阻色谱法测定介孔材料的孔结构  

Determination of pore size distributions of mesoporous materials by size-exclusion chromatography

作　　者：王志华[1] 吴利平[1,2] 连东[2,3] 张庆合[2] 李红梅[2] 

机构地区：[1]北京化工大学化工资源有效利用国家重点实验室,北京100029 [2]中国计量科学研究院化学计量与分析科学研究所,北京100013 [3]大庆市环境监测中心站,黑龙江大庆163316

出　　处：《化学试剂》2011年第2期97-101,共5页Chemical Reagents

基　　金：国家自然科学基金资助项目(20775075);科技部科技基础性工作专项资助项目(2008FY130200)

摘　　要：分别合成了球形的苯基桥键和乙烷桥键两种新型杂化介孔材料。选用已知平均相对分子质量且具有窄相对分子质量分布的葡聚糖为探针溶质,采用动态光散射法测定了粒径,与经验公式计算结果接近。通过体积排阻法对两种材料的孔隙率和孔径分布进行测定并与氮气吸附法结果进行比较,实现介孔材料孔结构快速测定。结果表明,体积排阻色谱法测定苯基桥键和乙烷桥键材料的平均孔径分别为1.14和2.08 nm,而氮气吸附法测定值分别为3.15和3.80 nm,可能是材料在水相介质中表面水合作用的结果,该方法能够更加准确反映色谱实际过程中孔径分布,同时该类新型介孔材料作为体积排阻色谱填料也表现出其优势。The spherical phenylene-bridged and ethane-bridged periodic mesoporous organosilica(PMOs) materials were prepared,respectively.Dextran of known average molecular weight and narrow molecular size distribution were selected as probe solutes.The particle sizes were determined by dynamic light scattering measurements,which were close to the results calculated by the empirical formula.The porosities and pore size distributions of two kinds of materials prepared in the laboratory were determined by the size-exclusion chromatography(SEC) and compared with the results of nitrogen adsorption measurements.The pore structure of mesoporous materials could be determined rapidly.The results showed that the mean pore size of the phenylene-bridged and ethane-bridged materials determined by size-exclusion chromatography was 1.14 nm and 2.08 nm,respectively,while that determined by nitrogen adsorption method was 3.15 nm and 3.80 nm,respectively.The difference in pore size measurements might be caused by the surface hydration of materials in the aqueous medium.This method can reflect the pore size distribution more accurately upon being adopted during the actual chromatographic analysis.Meanwhile,this new type of mesoporous materials demonstrates its advantages to be used as the gel chromatographic packing.

关 键 词：体积排阻色谱法 介孔材料 快速测定 孔结构 相对分子质量分布 平均相对分子质量 动态光散射法 氮气吸附法 

分 类 号：O657.7[理学—分析化学]