Preparation and Characterization of a New Negatively Charged PTFE Fiber Membrane for Separating Oil-in-water Emulsions Containing Cationic Emulsifiers

A new hydrophilicity and negatively charged polytetrafluoroethylene (PTFE) fiber membrane has been developed and characterized. Specifically, the dopamine (DA) and polyethylenimine (PEI) were co-deposited onto the PTFE fiber membrane surface via covalent connection. Then the amine groups of the membrane surface were reacted with anhydride groups of poly(ethylene-alt-maleic anhydride) (PEMA). Last, unreacted anhydride groups have hydrolysis and ionization. The preparation membrane has been investigated and confirmed by using XPS, ATR-FTIR, SEM, Zeta potential analyzer, pore size analyzer water contact angle, respectively. The results showed that the membranes were endowed with excellent hydrophilicity and negatively charged. It has high separation efficiency and permeation flux for oil-in-water emulsion containing cationic emulsifiers, and excellent anti-fouling property.