The nonsolvent thermally induced phase separation (N-TIPS) method is used to prepare flat sheet polypropylene membranes. The morphology and performance of the membranes prepared by standard TIPS and N-TIPS are compared. The effect of some parameters of membrane preparation process such as polymer concentration in dope solutions, thermodynamic affinity between the polymer and cosolvent and gap height in the film-casting device on the membrane structure and properties is investigated. The membrane properties can be controlled over a range of permeability values from 0.3 to 48 m3m–2h–1 bar–1 and mean through pore size from 0.22 to 0.55 μm.
