A PVDF membrane was prepared by isothermal immersion precipitation of a PVDF/NMP solution from pure water bath. FESEM imaging of the formed membrane revealed its porous structure, featuring tight skin, macrovoids, and cellular pores. These structural characteristics were common to membranes that were formed by precipitation of amorphous polymers from harsh nonsolvents. Evidence of crystallization in the present PVDF membrane could be observed on the surfaces of the various pores in the form of branching dendrites.
淡江理工學刊=Tamkang journal of science and engineering 5(2), pp.95-98