Effects of Peg Additives on Water Vapor Permeability of Porous PVDF Membranes

Porous polyvinylidene fluoride (PVDF) membranes with various structures were prepared via phase inversion using DMF as solvent. Polyethylene glycols (PEG) with three different concentrations and molecular weights were used. Effects of PEG on the structure and performance of porous membranes were investigated. The morphology and structure of the prepared membrane were characterized by scanning electron microscopy (SEM). The water vapor permeability through membranes was evaluated by permeation test. The results showed that PEG was used as pore forming agent in PVDF/DMF/H₂O system. Moreover, it has great influences on morphology and water vapor permeability. The membranes becomes more porous with PEG additives. Water vapor transfer resistance was reduced, which leads to improved water vapor permeability.