Investigation of corrugation phenomenon in the inner contour of hollow fibers during the non-solvent induced phase-separation process

CO 2 absorption using gas-liquid membrane contactors made of highly porous poly(vinyl chloride) hollow fiber membranes

“…Furthermore, in our recently published work (Fashandi et al, 2016), it was also demonstrated that delayed NIPS favors less corrugated inner surface. These observations concur with the studies of Bonyadi et al (2007) who investigated the corrugation phenomenon during HFM formation based on NIPS method.…”

Fabrication and Characterization of Polysulfone Membranes Coated with Polydimethysiloxane for Oxygen Enrichment

“…It is also found that the membrane wall thickness is in the order of PSF-1 > PSF-2 > PSF-3 with respect to the bore fluid flow rate. The increment of the hollow fiber membrane diameter and the decrease of the wall thickness are in good agreement with the literature findings where increasing bore fluid speed tended to have higher competitive force between the bore fluid liquid and dope solution in phase inversion process (Bonyadi et al, 2007). In this work, the formation of thin hollow fiber membrane is attributed to the rapid solidification of polymer arise from the high bore fluid flow rate although the inner and outer diameters of the spinneret remained constant.…”

The rheology of Torlon® solutions and its role in the formation of ultra-thin defect-free Torlon® hollow fiber membranes for gas separation

“…As the dope temperature increases, both the shear and elongational viscosities decrease exponentially, which may slow down the formation of the precipitation front and reduce the strength of the nascent outer surface of the fibers [21,[33][34][35]. As a consequence, the diffusion and convective flows of the nonsolvent at the fiber outer edge would be facilitated and hence the macrovoid formation is promoted [21,[35][36][37]. In terms of the phase inversion kinetics, as the temperature increases, the binodal curve would shift closer to the polymer-nonsolvent axis in the phase diagram.…”

“…10. The detailed experimental procedure has been described elsewhere [37] and the temperature of the polymer solution was adjusted by a hot plate. It can be observed from the photos that the nonsolvent convection takes place immediately after the occurrence of phase inversion (0.1 s) and is obviously accelerated at a higher dope temperature.…”