Model Simulation of Solvent Profile in the Preparation of PVDF Membrane and the Mechanism of Macrovoid Formation

Out diffusion behaviors of solvent in PVDF/Additive/DMAc dope solution were investigated using an improved immersion precipitation phase inversion method during membrane preparation.The mass content of PVDF in the dope was fixed as 15%.PEG200,PEG2000 and PVP were used as additives.Diffusion coefficient of solvent in the membrane was obtained from the experiment results by a curve fitting method.Using measured data as boundary condition,coordination transferred Fick's equation was(employed) to calculate the ...