Viscoelastic and gas transport properties of a series of multiblock copolymer ionomers

Yanfang Fan, Mingqiang Zhang, Robert B. Moore, Hae Seung Lee, James E. McGrath, Chris J. Cornelius

Research output: Contribution to journalArticlepeer-review

15 Scopus citations


A series of sulfonated poly(arylene ether sulfone) (BPSH-BPS) multiblock copolymer (MBC) ionomers were studied with respect to structure and physical properties. Ion exchange capacity (IECw) on a weight basis was constant for all MBC ionomers with controlled ionic and nonionic block lengths of 5k:5k, 10k:10k and 15k:15k. Viscoelastic properties were investigated as a function of block length, relaxation time, and temperature ranging from 200 °C to 250 °C. Relaxation time and glassy state modulus decreased with increasing ionic block length. Williams-Landel-Ferry (WLF) theory adequately modeled the viscoelastic changes in the BPSH-BPS MBC ionomers due to changes in time and temperature using a shift factor aT. Small Angle X-ray Scatter (SAXS) revealed an average inter-chain d-spacing that increased with increasing ionic block length (21.1, 31.4 and 36.4 nm). The larger ionic domain size is attributed to an increase in bulk ionic density within an ionic domain. Bondi's group contribution method predicts a lower fractional free volume (FFV) with increasing ionic block length. The 15k BPSH-BPS MBC ionomer had the lowest FFV of the series, which corresponds to the lowest hydrogen permeability of 2.46 Barrers at 30 °C and 4 atm.

Original languageEnglish (US)
Pages (from-to)3963-3969
Number of pages7
Issue number18
StatePublished - Aug 18 2011
Externally publishedYes


  • Ionomer
  • Transport
  • Viscoelasticity

ASJC Scopus subject areas

  • Organic Chemistry
  • Polymers and Plastics
  • Materials Chemistry


Dive into the research topics of 'Viscoelastic and gas transport properties of a series of multiblock copolymer ionomers'. Together they form a unique fingerprint.

Cite this