Preparation of UF membranes with polymeric additives

Ultrafiltration (UF) polymeric membranes were prepared from polyvinyldyne fluoride via phase inversion method induced by immersion precipitation. N,N-dimethylacetamide (DMAC), water, PEG200 and PVP were used as solvent, nonsolvent, additive1 and additive2 , respectively. Initial UF membrane includes additive1. PVP polymer additive was combined with PEG200 in different percentages. Flux, BSA Rejection, Porosity and SEM analysis were evaluated on the membrane. While permeated pure water flux increases with higher PVP percentages, rejection decreases since, even though the number of pores on the surface of the membrane grows, their size scales up, as well. The optimum amount of PVP to be solved in the solution, is the amount of which the rejection does not change significantly with flux increase. The optimized point for our case is PEG200 and PVP with 5 and 1 percentages, respectively