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Title: Polyimide-PEG Segmented Block Copolymer Membranes with High Proton Conductivity by Improving Bicontinuous Nanostructure of Ionic Liquid-Doped Films

Abstract

The structure and properties of segmented block copolymer films of aromatic polyimide (PI) and poly(ethylene glycol) (PEG) doped with an ionic liquid are observed for potential polymer electrolyte membrane applications for fuel cells. Poly(amic acid) precursors of PI-PEG copolymers of 4,4'-(hexafluoroisopropylidene) diphthalic anhydride, 4,4'-(1,3-phenylenedioxy) dianiline, and bis(3-aminopropyl) terminated PEG (Mn ≈ 1500) are synthesized and then thermally imidized in membrane films, followed by swelling in ethylammonium nitrate (EAN) ionic liquid. The small-angle X-ray scattering results from the EAN-doped PI-PEG copolymer films show disordered bicontinuous phase-separated nanostructures described by Teubner–Strey theory, with the interface fractal dimension determined from the Porod equation. Thermal annealing of the EAN-doped membranes at 100–140 °C results in increased correlation lengths and smoother interfaces of the bicontinuous nanostructures. Such improved nanostructures lead to the increased ionic conductivity by two to five times with the maximum conductivity of 210 mS cm-1 at 60 °C and 70% RH, much greater (nearly fivefold) than that of Nafion films, while maintaining the mechanical stability possibly up to 140 °C. Furthermore, the investigation of the disordered bicontinuous phase-separated nanostructure of EAN-doped PI-PEG copolymer membranes is highly relevant to understanding the nanostructures of hydrated Nafion membranes and segmented block copolymers in general.

Authors:
 [1];  [2];  [2];  [2];  [3]; ORCiD logo [2];  [2]
  1. Stanford Univ., CA (United States); Lotte Advanced Materials Co., Ltd., Uiwang‐si (Republic of Korea)
  2. Stanford Univ., CA (United States)
  3. SLAC National Accelerator Lab., Menlo Park, CA (United States)
Publication Date:
Research Org.:
SLAC National Accelerator Lab., Menlo Park, CA (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22); National Science Foundation (NSF)
OSTI Identifier:
1532506
Grant/Contract Number:  
AC02-76SF00515; 1511373
Resource Type:
Accepted Manuscript
Journal Name:
Macromolecular Chemistry and Physics
Additional Journal Information:
Journal Volume: 220; Journal Issue: 9; Journal ID: ISSN 1022-1352
Publisher:
Wiley
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; bicontinuous structures; ionic liquids; polymer electrolyte membranes; segmented block copolymers

Citation Formats

Woo, Euntaek, Coletta, Elyse, Holm, Alexander, Mun, Jaewan, Toney, Michael F., Yoon, Do Y., and Frank, Curtis W. Polyimide-PEG Segmented Block Copolymer Membranes with High Proton Conductivity by Improving Bicontinuous Nanostructure of Ionic Liquid-Doped Films. United States: N. p., 2019. Web. doi:10.1002/macp.201900006.
Woo, Euntaek, Coletta, Elyse, Holm, Alexander, Mun, Jaewan, Toney, Michael F., Yoon, Do Y., & Frank, Curtis W. Polyimide-PEG Segmented Block Copolymer Membranes with High Proton Conductivity by Improving Bicontinuous Nanostructure of Ionic Liquid-Doped Films. United States. doi:10.1002/macp.201900006.
Woo, Euntaek, Coletta, Elyse, Holm, Alexander, Mun, Jaewan, Toney, Michael F., Yoon, Do Y., and Frank, Curtis W. Wed . "Polyimide-PEG Segmented Block Copolymer Membranes with High Proton Conductivity by Improving Bicontinuous Nanostructure of Ionic Liquid-Doped Films". United States. doi:10.1002/macp.201900006. https://www.osti.gov/servlets/purl/1532506.
@article{osti_1532506,
title = {Polyimide-PEG Segmented Block Copolymer Membranes with High Proton Conductivity by Improving Bicontinuous Nanostructure of Ionic Liquid-Doped Films},
author = {Woo, Euntaek and Coletta, Elyse and Holm, Alexander and Mun, Jaewan and Toney, Michael F. and Yoon, Do Y. and Frank, Curtis W.},
abstractNote = {The structure and properties of segmented block copolymer films of aromatic polyimide (PI) and poly(ethylene glycol) (PEG) doped with an ionic liquid are observed for potential polymer electrolyte membrane applications for fuel cells. Poly(amic acid) precursors of PI-PEG copolymers of 4,4'-(hexafluoroisopropylidene) diphthalic anhydride, 4,4'-(1,3-phenylenedioxy) dianiline, and bis(3-aminopropyl) terminated PEG (Mn ≈ 1500) are synthesized and then thermally imidized in membrane films, followed by swelling in ethylammonium nitrate (EAN) ionic liquid. The small-angle X-ray scattering results from the EAN-doped PI-PEG copolymer films show disordered bicontinuous phase-separated nanostructures described by Teubner–Strey theory, with the interface fractal dimension determined from the Porod equation. Thermal annealing of the EAN-doped membranes at 100–140 °C results in increased correlation lengths and smoother interfaces of the bicontinuous nanostructures. Such improved nanostructures lead to the increased ionic conductivity by two to five times with the maximum conductivity of 210 mS cm-1 at 60 °C and 70% RH, much greater (nearly fivefold) than that of Nafion films, while maintaining the mechanical stability possibly up to 140 °C. Furthermore, the investigation of the disordered bicontinuous phase-separated nanostructure of EAN-doped PI-PEG copolymer membranes is highly relevant to understanding the nanostructures of hydrated Nafion membranes and segmented block copolymers in general.},
doi = {10.1002/macp.201900006},
journal = {Macromolecular Chemistry and Physics},
number = 9,
volume = 220,
place = {United States},
year = {2019},
month = {4}
}

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Works referenced in this record:

Proton exchange membrane fuel cell from low temperature to high temperature: Material challenges
journal, May 2007


Effects of aromatic regularity on the structure and conductivity of polyimide-poly(ethylene glycol) materials doped with ionic liquid
journal, January 2015

  • Coletta, Elyse; Toney, Michael F.; Frank, Curtis W.
  • Journal of Polymer Science Part B: Polymer Physics, Vol. 53, Issue 7
  • DOI: 10.1002/polb.23664

Gas transport properties of poly(ether-b-amide) segmented block copolymers
journal, January 2000


Synthesis and Characterization of Polysulfone-Containing Poly(butylene terephthalate) Segmented Block Copolymers
journal, November 2014

  • Dennis, Joseph M.; Fahs, Gregory B.; Moore, Robert B.
  • Macromolecules, Vol. 47, Issue 23
  • DOI: 10.1021/ma501903h

Polymer-Polymer Phase Behavior
journal, February 1991


Ionic Conductivity of an Extruded Nafion 1100 EW Series of Membranes
journal, January 2002

  • Slade, S.; Campbell, S. A.; Ralph, T. R.
  • Journal of The Electrochemical Society, Vol. 149, Issue 12
  • DOI: 10.1149/1.1517281

Recent developments in high-temperature proton conducting polymer electrolyte membranes
journal, March 2003


Approaches and Recent Development of Polymer Electrolyte Membranes for Fuel Cells Operating above 100 °C
journal, December 2003

  • Li, Qingfeng; He, Ronghuan; Jensen, Jens Oluf
  • Chemistry of Materials, Vol. 15, Issue 26
  • DOI: 10.1021/cm0310519

From Homogeneous to Heterogeneous Nucleation of Chain Molecules under Nanoscopic Cylindrical Confinement
journal, March 2007


Crystalline Structures, Melting, and Crystallization of Linear Polyethylene in Cylindrical Nanopores
journal, September 2007

  • Shin, Kyusoon; Woo, Euntaek; Jeong, Young Gyu
  • Macromolecules, Vol. 40, Issue 18
  • DOI: 10.1021/ma070994e

Phase Segregation and Gas Separation Properties of Thermally Treated Copoly(ether-imide) from an Aromatic Dianhydride, an Aromatic Diamine, and Various Aliphatic Diamines
journal, February 2012

  • Tena, Alberto; Marcos-Fernández, Angel; Palacio, Laura
  • Industrial & Engineering Chemistry Research, Vol. 51, Issue 9
  • DOI: 10.1021/ie2028443

Recent developments in fuel-processing and proton-exchange membranes for fuel cells
journal, October 2010

  • Bai, He; Ho, WS Winston
  • Polymer International, Vol. 60, Issue 1
  • DOI: 10.1002/pi.2936

Selective Permeation of Carbon Dioxide over Nitrogen through Polyethyleneoxide-Containing Polyimide Membranes
journal, February 1993

  • Okamoto, Ken-ichi; Umeo, Nobuhiro; Okamyo, Shuusaku
  • Chemistry Letters, Vol. 22, Issue 2
  • DOI: 10.1246/cl.1993.225

Origin of the scattering peak in microemulsions
journal, September 1987

  • Teubner, M.; Strey, R.
  • The Journal of Chemical Physics, Vol. 87, Issue 5
  • DOI: 10.1063/1.453006

Simulation of bicontinuous microemulsions: comparison of simulated real-space microstructures with scattering experiments
journal, October 1991


Die Röntgenkleinwinkelstreuung von dichtgepackten kolloiden Systemen: I. Teil
journal, November 1951


Parallel cylindrical water nanochannels in Nafion fuel-cell membranes
journal, December 2007

  • Schmidt-Rohr, Klaus; Chen, Qiang
  • Nature Materials, Vol. 7, Issue 1
  • DOI: 10.1038/nmat2074

Studying orthogonal self-assembled systems: microstructure of gelled bicontinuous microemulsions
journal, January 2014

  • Laupheimer, Michaela; Sottmann, Thomas; Schweins, Ralf
  • Soft Matter, Vol. 10, Issue 43
  • DOI: 10.1039/C4SM01639D

Application of Ionic Liquids to Energy Storage and Conversion Materials and Devices
journal, January 2017


Protic Ionic Liquid-Based Hybrid Proton-Conducting Membranes for Anhydrous Proton Exchange Membrane Application
journal, March 2010

  • Lin, Bencai; Cheng, Si; Qiu, Lihua
  • Chemistry of Materials, Vol. 22, Issue 5
  • DOI: 10.1021/cm9033758

Morphology of Hydrated As-Cast Nafion Revealed through Cryo Electron Tomography
journal, December 2014

  • Allen, Frances I.; Comolli, Luis R.; Kusoglu, Ahmet
  • ACS Macro Letters, Vol. 4, Issue 1, p. 1-5
  • DOI: 10.1021/mz500606h