Modification of the surface of polyvinylidene fluoride membranes with polyethyleneimine

PVDF membranes are extensively applied in ultrafiltration processes of aqueous solutions different chemical substances owing to its outstanding properties, such as high mechanical strength, thermal stability, and resistance. However, hydrophobicity this polymer largely limits the practical application PVDF. Therefore, it is very important develop methods modifying surface with aim improve their properties. Polyethyleneimine, a agent, has already been investigated for hydrophilization surface. modification process leads reduction volumetric flow changes membrane selectivity because grafted not only surface, but also into pores membranes, reducing effective radius. Taking everything account, investigation devoted development technique PEI (with pre-filling pores) transport at same time preserving morphology characteristics. Nonionic surfactant Tetronic® 701 used pore-filling agent. Commercial cut-off 150 kDa) were firstly activated carbonate buffer, then filled 701, further was performed. The confirmed by IR spectroscopy. properties studied scanning electron microscopy. hydrophilicity modified measuring wetting angles water, glycerol, diiodomethane. experimentally protein solution (in particular, lysozyme, lipase, BSA); water permeability coefficients rejection determined. It found that usage during allowed improving coefficient compared without pores; reduced effect concentration polarization.