skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

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); National Science Foundation (NSF)
OSTI Identifier:
1532506
Grant/Contract Number:  
AC02-76SF00515; 1511373
Resource Type:
Journal Article: 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. https://doi.org/10.1002/macp.201900006
Woo, Euntaek, Coletta, Elyse, Holm, Alexander, Mun, Jaewan, Toney, Michael F., Yoon, Do Y., and Frank, Curtis W. 2019. "Polyimide-PEG Segmented Block Copolymer Membranes with High Proton Conductivity by Improving Bicontinuous Nanostructure of Ionic Liquid-Doped Films". United States. https://doi.org/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},
url = {https://www.osti.gov/biblio/1532506}, journal = {Macromolecular Chemistry and Physics},
issn = {1022-1352},
number = 9,
volume = 220,
place = {United States},
year = {Wed Apr 03 00:00:00 EDT 2019},
month = {Wed Apr 03 00:00:00 EDT 2019}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record

Citation Metrics:
Cited by: 3 works
Citation information provided by
Web of Science

Save / Share:

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


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


Polymer-Polymer Phase Behavior
journal, February 1991


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


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


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


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


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


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


Origin of the scattering peak in microemulsions
journal, September 1987


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


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


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


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


Die Röntgenkleinwinkelstreuung von dichtgepackten kolloiden Systemen
journal, October 1953