聚偏氟乙烯中空纤维膜的低温等离子体改性及动电特性研究

ELECTROKINETIC BEHAVIOR ON THE SURFACE OF PVDF HOLLOW FIBER MEMBRANE MODIFIED BY USING LOW-TEMPERATURE PLASMA METHOD

采用低温等离子体设备改性聚偏氟乙烯(PVDF)中空纤维膜,以接枝率、力学性能、膜面元素含量的变化以及膜面形态为评价指标考察改性膜物理及化学特性的变化,并研究了改性膜的清水通量及膜面的动电特性。元素能谱分析表明,经丙烯酰胺(AM)接枝改性后膜表面的N、O含量明显增加。SEM照片及拉力试验反映出改性膜的膜孔径变小,力学性能良好。改性膜的荷电性能明显优于原膜,且接枝单体质量分数为5%的改性膜的清水通量大于原膜。

There were used acryl amide AM to modified by low-temperature plasma treatment and graft copolymerization. Their effects on the chemistry structure and morphology straeture of the membrane surface have been studied by SEM and EDS. Moreover the mechanical property membrane was investigated and compared. The results showed that the large of O,N have been introduced. The mechanical property of PVDF not decreased after modify. Streaming potential measurements have been used to investigate the surface characteristics of modified membrane and original membrane by the equipment for streaming potential measurement which was made in our laboratory. The ζ potentials and charge density of the membranes were calculated from the streaming potential by using helmholtz-smoluchowski equation and gouy-chapmann equation, respectively. The results show that the ζ potential and charge density of modified membranes were superior to virgin membranes.