Fabrication of fluoropolyimide/polyethersulfone (PES) dual-layer asymmetric hollow fiber membranes for gas separation

Dong Fei Li, Tai Shung Chung*, Rong Wang, Ye Liu

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

123 Scopus citations


By using co-extrusion and dry-jet wet-spinning phase inversion techniques, we have developed delamination-free dual-layer asymmetric composite hollow fiber membranes for gas separation. Delamination-free is essential for dual-layer membranes to withstand high testing pressures. For concept demonstration, a 6FDA-durene-1,3-phenylenediamine (mPDA) (50:50) copolyimide was used to form the outer asymmetric separating layer, while polyethersulfone (PES) was employed to yield the inner interpenetrated porous supporting layer. A special assembly for outer-layer dope passage was firstly introduced into the dual-layer spinneret design in order to enhance the uniformity of dope distribution in nozzle orifice. A much thinner (≈ 10 μm) and uniform outer layer was achieved. The effects of spinning conditions, such as spinneret temperature, air gap, bore fluid chemistry, inner-layer dope concentration and formulation, and solvent exchange on the interface delamination between the dual layers were examined. Inner-layer dope concentration and bore fluid composition as well as the sequent solvent exchange were found to play important roles to produce delamination-free dual-layer membranes. Pure gas test results show that the resultant 6FDA-durene-mPDA/PES dual-layer membranes have an O2/N2 selectivity approaching to the intrinsic ideal selectivity value of 4.7 with a permeance of oxygen around 28 GPU (gas permeance unit) at room temperature, indicating the dual-layer hollow fiber membranes are apparently defect-free.

Original languageEnglish (US)
Pages (from-to)211-223
Number of pages13
JournalJournal of Membrane Science
Issue number2
StatePublished - Apr 15 2002
Externally publishedYes

Bibliographical note

Funding Information:
The authors would like to thank British Gas Technology, Institute of Materials Research and Engineering, Environmental Technology Institute and National Science Technology Board of Singapore for funding the project (research fund no. 113006). Special thanks are extended to Miss M.L. Chng, Miss W.W. Loh and Ms. L.K. Leong for their help.


  • Air separation
  • Composite hollow fiber membranes
  • Dual-layer membranes
  • Gas separation

ASJC Scopus subject areas

  • Biochemistry
  • General Materials Science
  • Physical and Theoretical Chemistry
  • Filtration and Separation


Dive into the research topics of 'Fabrication of fluoropolyimide/polyethersulfone (PES) dual-layer asymmetric hollow fiber membranes for gas separation'. Together they form a unique fingerprint.

Cite this