Surface modification of polysulfone membrane by low temperature plasma treatment

The positive charge was introduced on polysulfone (HT) membrane with negative surface charge by low temperature plasma initiating graft polymerization of 2-(dimethylamine) ethyl methacrylates (DMAEMA). It was confirmed by the X-ray photoelectron spectra (XPS) results that the introduction of positive charge group. Surface charge of the membrane was determined by measuring electroosmotic flux across the membrane. The effects of operation parameters including treatment power, treatment time, and polymerization time on the modification process were examined. The results also showed that surface modification by low temperature plasma, as described in the present paper, effectively reduced the net negative charge of membrane surface, and moreover, the adsorption of lysozyme on the membrane surface.