等离子体改性PVDF中空纤维超滤膜的动电性质研究

为减轻膜污染以丙烯酸和丙烯酰胺为接枝单体，对聚偏氟乙烯中空纤维超滤膜用低温等离子体方法进行改性。用流动电位法，测定电解质溶液中膜的流动电位并研究电解质溶液的种类、浓度及pH值的影响，对比改性前后的膜流动电位变化情况。结果表明，流动电位绝对值随着电解质浓度的增大而减小，随着电解质溶液中阳离子价态的升高而减小；改性后膜的zeta电位略高于原膜。

Surface Electrokinetic Behavior of PVDF Hollow Fiber Ultrafiltration Membrane Modified by Low- Temperature Plasma Method

Polyvinylidene fluoride（PVDF）hollow -fiber membrane was modified by low -temperature plasma graft treatment to reduce the membrane polution. The acrylic acid（AA） and the acrylic amide （AM）were used as grafting monomers. The streaming potentials of these membranes were measured in the solutions of different electrolytes with different concentrations and different pH values. The streaming potentials of modified membrane were compared with un - modified one. The result of experiment shows that the absolute values of streaming potentials decreases when electrolyte concentrations increases; the higher the cationic valences is, the lower the streaming potential is; the zeta potential of the modified membrane is higher than the un - modified membrane.