Abstract:In this work, microporous membranes were prepared using polyvinylidene fluoride (PVDF) and dimethylacetamide as the solvent via non-solvent induced phase separation technique. The effects of dope compositions (i.e., various additives) and phase change conditions (i.e., evaporation time and relative humidity) on the membrane structure and performance were systematically investigated. It was found that hydrophobic PVDF membranes with large pore size and high permeance could be obtained by adding 16 wt.% isopropanol and 6 wt.% glycerol in the dope solution, followed by evaporation for 4 min at RH 80% before being immersed in water. The membrane possessed a completely open surface and bicontinuous interconnected structure, which contribute to little resistance in the filtration processes. The prepared PVDF membranes showed high pure water flux of 8650.74 LMH after pre-wetting and 200nm-polystyrene-microspheres rejection of more than 99%. In addition, the membrane was hydrophobic with water contact angle of 122°, which make the membrane as a promising candidate used for gas sterilization in the bio-pharmaceutical manufacturing process.