Surface modification of functionalized multiwalled carbon nanotubes containing mixed matrix membrane using click chemistry

Abstract

Surface modification of mixed matrix membranes is especially challenging because functional groups on the surface are not precisely known. This study describes a novel concept of modification of the membrane surface by the reaction of the azide functionalized multiwalled carbon nanotubes mixed matrix membranes of polyether sulfone. The surface azide groups were reacted with terminal alkyne 1-pentyne, using the Cu(I) catalyzed [3 + 2] Huisgen cycloaddition. XPS confirmed the presence of the triazole group, typical of the ‘click reaction’, on the surface of the membrane. The surface hydrophilicity, wettability and water permeability were enhanced in the modified membrane. The water flux of the surface modified membrane increased reaching a maximum of 331.2 L/m2 h, while the rejection performance for heavy metals was comparable to the unmodified membrane. The BSA adsorption of the surface modified triazole containing membrane was considerably reduced, indicating an enhanced surface hydrophilicity. Surface hydrophilicity and porous structure of the membrane are factors for improved membrane performance and limiting the protein adsorption which indicates an enhanced fouling resistance.