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چکیده
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Consistently the membrane performance is limited by membrane fouling through the decrement of water flux and degradation of water quality. Many efforts have been devoted to solve the membrane fouling problem. A large part of researches are about the development of antifouling membrane surface constructed by various hydrophilic polymers and nanomaterials. Now we have designed a new functionalized MWCNT based on a well-known thermoresponsive and hydrophilic (at 25°C) polymer to overcome the membrane fouling problem. The poly(N-isopropylacrylamide) (PNIPAAm) is a thermo-responsive polymer with the low critical solution temperature (LCST) about 33 °C in an aqueous solution. The thermo-responsive behavior of PNIPAAm is based on the response to the ambient temperature and subsequently changes in conformation of polymer. The changeable state in the surface with the thermo-responsive material, creates the unstable condition for located foulant. In the low temperature (below the LCST, 25°C) thermo-responsive polymer is in the hydrophilic state with the extended chain structure. On the other hand, with the temperature rising to above the LCST, PNIPAAm becomes hydrophobic with the shrinkage structure. These changeable structures provide the fouling release surface for the membrane. In this study, firstly, The MWCNT-PNIPAAm nano-composite was synthetized via free radical polymerization and then was added to the membrane matrix polyethersolfone (PES) by the physical blending method. Then we examined the fouling of a functionalized MWCNT membrane with diary waste treatment.
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