受贻贝启发的油水分离材料的制备及应用

Mussels-inspired Preparation and Application of Oil/Water Separation Materials

受海洋生物贻贝的超强黏附力的启发,通过简单的表面修饰,成功制备出具有高效油水分离性能的改性聚四氟乙烯滤膜.首先,在弱碱性条件下,多巴胺(DA)在聚四氟乙烯(PTFE)滤膜表面室温下自聚生成聚多巴胺(PDA);然后,在pH=13的条件下,1–癸硫醇与聚多巴胺发生Michael加成反应,使疏水基团通过化学键连接到聚多巴胺上;最终经过表面改性,聚多巴胺滤膜的浸润性发生改变,成功制备出疏水亲油的改性聚四氟乙烯滤膜.改性聚四氟乙烯滤膜表面水的接触角为114.9°,油的接触角为0°.孔径为2μm的改性聚四氟乙烯滤膜通量高达4159.7 L/(m2·h),不同种类油的油水分离效率均在96.7%以上,重复分离20次后,通量最大衰减率仅为4.4%.在4 mol/L的盐酸或氢氧化钠溶液中浸泡12 h后,改性聚四氟乙烯滤膜的通量维持在3976.7 L/(m2·h)以上.因此,改性聚四氟乙烯滤膜有望应用于极端恶劣环境下的油水分离.

Inspired by the strong adhesion of marine mussels,we have successfully prepared modified polytetrafluoroethylene(PTFE)membranes with high efficiency of oil-water seperation performance through simple surface modification.Firstly,dopamine(DA)self-polymerized on the surface of polytetrafluoroethylene(PTFE)membrane to form polydopamine(PDA)in weak alkalinity solution at room temperature.Then,hydrophobic groups were introduced to polydopamine by chemical bonds when pH was 13 and polydopamine was reacting with 1-decathiol via Michael addition.Finally,after surface modification,the wettabilities of PDA membranes changed,and oleophilic hydrophobic modified polytetrafluoroethylene membranes were prepared.The water contact angle on the modified PTFE surface is 114.9°and its oil contact angle is 0°.The flux of modified PTFE filtration membranes with the pore diameter of 2μm reaches 4159.7 L/(m2·h).The oil/water separation efficiency for different oils is all above 96.7 percent.After 20 times of repeated separation,the maximum flux decreasing rate is only 4.4%.After immersion in 4 mol/L hydrochloric acid or sodium hydroxide solution for 12 h,the flux of modified PTFE membranes is still above 3976.7 L/(m2·h).Therefore,the modified PTFE membranes are promising for oilwater separation in extreme environments.