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A well-defined water-soluble superamphiphilic block copolymer surfactant containing superhydrophilic zwitterionic and very hydrophobic long alkyl units (PSbPDz) was synthesized via reversible addition-fragmentation chain-transfer polymerization for the replacement of the conventional surfactant used to polyamide (PA) thin-film reverse osmosis (RO) membrane. PSbPDz was found to act as a surfactant successfully, and work as a filler at the same time even after interfacial polymerization (IP) due to its entanglement effect of the polymer chains with the PA matrix. As the surfactant, PSbPDz improves the water wettability on the top surface of the support layers decreasing the thickness of the PA selective layer at the thinnest region and expands the interface area between the aqueous and organic phase increasing the roughness of the PA selective layer. As the filler, PSbPDz introduced into the PA selective layer increases the water wettability of the RO membrane. Hence, the RO membrane fabricated with 0.015 wt% of PSbPDz in the aqueous solution through IP shows much larger water permeance value (1.69 L m−2 h−1 bar−1) than the neat RO membrane (0.68 L m−2 h−1 bar−1) maintaining the high salt rejection value.

In this study, hexagonal boron nitride nanosheets grafted with aliphatic groups (Alkyl-BN) were synthesized by a sonication-assisted alcoholysis reaction using hexagonal boron nitride (hBN) with 1-dodecanol, and a series of polypropylene (PP) nanocomposites were prepared by mixing PP with different amount of Alkyl-BN. The PP/Alkyl-BN nanocomposite containing a very small amount of Alkyl-BN showed much improved mechanical properties than those of neat PP and PP/hBN nanocomposites. For instance, Young's modulus value of PP/Alkyl-BN nanocomposite containing 0.5 wt% of Alkyl-BN is larger than that of neat PP by 17.5% while that of PP/hBN nanocomposite containing 0.5 wt% of hBN is larger by only 1.2%. The tensile strength value of PP/Alkyl-BN was found to be larger than that of the neat PP by 7.4% due to the enhanced interfacial interaction between Alkyl-BN and PP chains. Furthermore, the PP/Alkyl-BN nanocomposites exhibited enhanced thermal conductivity and stability than the neat PP and PP/hBN nanocomposite. This research clearly shows that the improved thermal and mechanical properties of polymer nanocomposites can be achieved with a very low filler content by the enhancement of the interfacial interaction between the filler materials and the polymer matrix.