Thickness Dependence of Macrovoid Evolution in Wet Phase-Inversion Asymmetric Membranes

Dongfei Li, Tai Shung Chung*, Jizhong Ren, Rong Wang

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

96 Scopus citations


Following an inspiration from Vogrin et al. (J. Membr. Sci. 2002, 207, 139), we have investigated the thickness dependence of macrovoid evolution during the phase inversion of asymmetric flat membranes and observed, for the first time, a critical structure-transition thickness, Lc, which indicates a transition of the membrane morphology from a spongelike to a fingerlike structure with an increase in membrane thickness. Below L c, the membranes show a fully spongelike cross-sectional structure, whereas above Lc, the membranes exhibit a mainly fingerlike macrovoid structure. Two binary solutions are employed in this study: 20 wt % polyethersulfone/N-methyl-2-pyrrolidone (NMP) and 20 wt % BTDA-MDI/TDI co-polyimide/NMP solutions. Their corresponding critical thicknesses, L c, are 1.5 ± 0.4 and 11 ± 2 μm, respectively.

Original languageEnglish (US)
Pages (from-to)1553-1556
Number of pages4
JournalIndustrial and Engineering Chemistry Research
Issue number6
StatePublished - Mar 17 2004
Externally publishedYes

ASJC Scopus subject areas

  • General Chemistry
  • General Chemical Engineering
  • Industrial and Manufacturing Engineering


Dive into the research topics of 'Thickness Dependence of Macrovoid Evolution in Wet Phase-Inversion Asymmetric Membranes'. Together they form a unique fingerprint.

Cite this