In this work, for the first time, porous Matrimid (R) 5218 membranes were prepared by employing a combination of vapour induced phase separation (VIPS) and non-solvent induced phase separation (NIPS) technique. N-methyl-2-pyrrolidone (NMP) and Rhodiasolv (R) Polarclean were used as a traditional and new green solvent, respectively, for the preparation of the membranes. Ternary phase diagrams with both solvents were preliminary carried out. The exposure time to humidity and the effect of polymer concentration on membrane morphology and properties were evaluated. The resulting membranes were fully characterized in terms of morphology, shrinkage propensity, thickness, porosity, mechanical properties, pore size, contact angle and water permeability.