Polyvinylidenefluoride/carbon nanotubes mixed matrix membranes with tailored properties

Membrane operations are promising tools for efficient and environmentally friendly separations. However, the development of advanced membranes with tailored properties is a key issue to be addressed in order to better exploit the potentialities of membrane-based separations. An important approach toward this aim is the development of mixed matrix membranes in which an organic and an inorganic phase coexist in order to have synergic effects on membrane properties. The peculiar properties of carbon nanotubes (CNTs) such as high electrical and thermal conductivity, high strength and unique transport properties, has motivated a considerable effort to produce CNT-polymer composites in order to engineer membrane properties. In this work the roughness, wettability, morphology, crystalline phase and pore size of polyvinylidenefluoride (PVDF) membranes were tailored working on the membrane preparation conditions, as well as, by blending the polymer with multiwalled carbon nanotubes (MWCNTs). A study on the effect of concentration of the polymer, use of pore forming additives, type and concentration of MWCNTs (pristine and functionalized), was carried out. The results highlighted interesting relationships between membrane microstructure and composition, as well as, MWCNTs distribution, on transport and wettability properties, in the perspectives of a more efficient application of PVDF membranes in liquid phase separations.