Microstructure in selective layer has played a decisive role in permselectivity of nanofiltration (NF) membranes

and nanomaterials were well-known additives that had been applied to mediate the microstructure and permeability of polyamide NF membranes. However

nanoadditives generally displayed a poor dispersion in membranes or in fabrication process. To solve this problem

we showed an interesting concept that novel NF membranes with hybrid selective layer consisting of flexible polyisobutylene (PIB) and rigid polyamide could be fabricated fromwell-defined interfacial polymerization. The hydrophobic polymer mediated phase separation andmicrodomains formation in polyamide layerwere found. The immiscibility between the rigid polyamide and flexible PIB as well as the resultant interface effect was interpreted as the reason for the polymer enhanced permselectivity

which was similar with the well-known thin film nanocomposite (TFN) membranes that nanoparticles incorporated contributed significantly to membrane permeability and rejection performance. Our results have demonstrated that novel NF membranes with enhanced performance can be prepared fromimmiscible polymers

which is a new area that has not been extensively studied before.