Industrial & Engineering Chemistry Research, Vol.54, No.16, 4174-4182, 2015
Polymerization and Functionalization of Membrane Pores for Water Related Applications
Poly(vinylidene fluoride) (PVDF) was modified by chemical treatments in order to create active double bonds to obtain covalent grafting of poly(acrylic acid) (PAA) on membrane. The attenuated total reflectance Fourier transform infrared (ATR-ETIlt) 'spectrum confirms the formation of conjugated' C=C double bonds with surface dehydrofluorination. The membrane' morphology was studied by scanning electron microscopy (SEM). The surface composition was characterized by X-ray photoelectron spectroscopy (XPS). The thermal stability of the dehydrofluorinated membrane (Def-PVDF) and functidnalized membranes were investigated by differential scanning,calorimetry (DSC) analysis. The influence of covalemly attached PAA on Def PVDF membrane has been investigated to determine its effect on the transport of water and charged solute. VariationS in the solution pH show an effect on both permeability and,Solute retention in a reversible fashion. Metal nanopafficles were also immobilized in the membrane for the degradation Of toxic chlorinated organics from water. In addition, PVDF Membranes with ariasymmetric and sponge-like Morphology were developed by immersion-precipitation phase-inversion ihethodsin both lab-scale and large-scale. The new type of spongy PVDF-rnembrane shows high surface area with higher yield of PAA functionalization. The ion-capacity with Ca2+ ions was also investigated.