Effective filtration ability with preventing irreversible biofilm formation might be the essential characteristic of water purification membranes. The materials used in current market still need the improvement to be more practical and durable for the high performance filtration technology. Nanofiltration, which is one of the method of water filtration, the materials for this use reguire highly defined nanostrucured morphology. In this study, we synthesized amphiphilic copolymers and blended with some homopolymers, of which the homopolymer could interact with a part of the copolymer by secondary interactions. Latet, the homopolymer was able to be removed, therefore, porous structure could be created. Also, the cell adhesion experiment of these polymer blend samples indicated anti-fouling effect of them.

We have studied ternary polymer blend system (A-B/C), which A and C polymers have attractive interactions. The blend was prepared as thin layer coating on the top of the supporting membrane, such as alumina, by layer-by-layer deposition of each polymer from the diluted solution. By controlling the fraction of polymer, the morphology of the blend showed various states including inter-connected porous structure at a certain condition. In addition, we tried to have the better control in pore size and function by introducing small molecule-containing layers atop of the blended coating. The selectivity of filtering and flux of the coated membrane was studied by filtration experiments with aqueous mixtures of various sized solutes including inorganic and organic compounds. Beneficially, the active layer coating exhibited anti-fouling effect.