The Influence of Solvents on the Characteristics of Polyethersulfone Membranes and the Conformational State of the Polymer When Using PVP as an Additive in the Casting Solution

In this work, polyethersulfone (PES) 5200 microfiltration membranes were obtained by phase inversion. The role of the solvent on the conformational changes occurring in polymer solutions, particle sizes, and characteristics of membrane samples was studied when different amounts of polyvinylpyrrolidone (PVP) K30 were added as an additive. In PES/DMF and PES/DMA compositions with 15% PES, 3%, 5%, and 7% by weight of PVP were added. It has been established that the addition of PVP to the unmodified compositions leads to an increase in the pure water flux of the precipitated membranes in the case of membranes precipitated from both solvents, but membranes precipitated from dimethylformamide have higher performance indicators and pore size values. Of the obtained membranes, the P7 membrane precipitated from a PES/DMF/7%PVP solution has better characteristics, PWF and structure.