基于气-液置换方式的毛细管流动孔径分析仪及其应用

Application of capillary flow porometer based on gas-liquid replacement method

介绍了毛细管流动孔径分析仪的原理,提出影响孔径数据的测试条件。以聚偏氟乙烯中空纤维膜为实验对象,考察测试条件如浸润方式、浸润液类型及时间、氮气升压速率等对孔径结果的影响,根据孔径相对标准偏差(RSD)确定测试条件。采用低表面张力porefil浸润液超声浸润、浸润时间10min、升压速率50mbar/s的最佳测试条件,PVDF膜泡点压力、最大孔径、平均孔径及最小孔径的相对标准偏差均低于5%,保证了测量结果的准确性。毛细管流动孔径分析仪采用气-液置换测试方式,直接测量膜贯通孔的孔喉直径,测试过程气体压力较低,可实现多次无损伤测量,使测量结果更准确。

The measurement principle of capillary flow porometer was described.The effects such as immersion method,wetting liquid,and immersion time,nitrogen pressure-rise rate on membrane pore size were studied.Using gas-liquid replacement method,the capillary flow porometer can directly measure pore throat size of interconnected membrane pore,and the measurement gas pressure is low,which makes the sample no damaged,and the measurement result more accurate.