Study of The Influence of Viscosity on The Morphology of Polyethersulfone Hollow Fiber Membranes/Additives

Abstract

The aim of this work was to prepare hollow fiber membrane changing the composition of polyethersulfone, polyvinylpyrrolidone (PVP) and clay, through the phase inversion technique, evaluating the influence of these constituents on the viscosity and distinct morphologies. Flat membranes were produced and their contact angles were determined and showed difference when clay was added and/or PVP. For the hollow fiber membranes, the +addition of these constituents, PVP and/or clay in the solution, can change significantly the viscosity and effect the membrane formation. From the scanning electron microscopy (SEM) images, it was identified the influence on morphology with the compositional variation of each additive, with the PVP promoting shorter precipitation time, favoring the formation of pores of the "fingers" type and increasing the presence of macrovoids. The addition of clay favored the formation of spherical pores, reducing the presence of macropores.

Preparation of Lateral Flow PVDF Membrane via Combined Vapor- and Non-Solvent-Induced Phase Separation (V-NIPS)

“…At this time, PVP is a high-molecular-weight additive, which increases viscosity, and delays the phase separation. After partially aggregated PVP is eluted, a large cavity shape appears [ 12 , 13 ].…”