Skip to main content

Thank you for visiting You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

Self-assembled highly ordered acid layers in precisely sulfonated polyethylene produce efficient proton transport


Recent advances in polymer synthesis have allowed remarkable control over chain microstructure and conformation. Capitalizing on such developments, here we create well-controlled chain folding in sulfonated polyethylene, leading to highly uniform hydrated acid layers of subnanometre thickness with high proton conductivity. The linear polyethylene contains sulfonic acid groups pendant to precisely every twenty-first carbon atom that induce tight chain folds to form the hydrated layers, while the methylene segments crystallize. The proton conductivity is on par with Nafion 117, the benchmark for fuel cell membranes. We demonstrate that well-controlled hairpin chain folding can be utilized for proton conductivity within a crystalline polymer structure, and we project that this structure could be adapted for ion transport. This layered polyethylene-based structure is an innovative and versatile design paradigm for functional polymer membranes, opening doors to efficient and selective transport of other ions and small molecules on appropriate selection of functional groups.

Access options

Rent or Buy article

Get time limited or full article access on ReadCube.


All prices are NET prices.

Fig. 1: Conductivity and water uptake of p21SA.
Fig. 2: X-ray scattering characterization of p21SA.
Fig. 3: Simulation results for the p21SA hydrated layered structure.
Fig. 4: Water dynamics from simulations of bulk water, MeSO3H solution, crystalline p21SA and amorphous p21SA.


  1. 1.

    Dobson, C. M. Protein folding and misfolding. Am. Sci. 90, 445–453 (2002).

    Article  Google Scholar 

  2. 2.

    Hill, D. J., Mio, M. J., Prince, R. B., Hughes, T. S. & Moore, J. S. A field guide to foldamers. Chem. Rev. 101, 3893–4011 (2001).

    Article  Google Scholar 

  3. 3.

    Ortmann, P. & Mecking, S. Long-spaced aliphatic polyesters. Macromolecules 46, 7213–7218 (2013).

    Article  Google Scholar 

  4. 4.

    Le Fevere de Ten Hove, C., Penelle, J., Ivanov, D. A. & Jonas, A. M. Encoding crystal microstructure and chain folding in the chemical structure of synthetic polymers. Nat. Mater. 3, 33–37 (2004).

    Article  Google Scholar 

  5. 5.

    Atallah, P., Wagener, K. B. & Schulz, M. D. ADMET: the future revealed. Macromolecules 46, 4735–4741 (2013).

    Article  Google Scholar 

  6. 6.

    Gaines, T. W., Trigg, E. B., Winey, K. I. & Wagener, K. B. High melting precision sulfone polyethylenes synthesized by ADMET chemistry. Macromol. Chem. Phys. 217, 2351–2359 (2016).

    Article  Google Scholar 

  7. 7.

    Caire da Silva, L., Rojas, G., Schulz, M. D. & Wagener, K. B. Acyclic diene metathesis polymerization: history, methods and applications. Prog. Polym. Sci. 69, 79–107 (2017).

    Article  Google Scholar 

  8. 8.

    Baughman, T., Chan, C., Winey, K. & Wagener, K. B. Synthesis and morphology of well-defined poly(ethylene-co-acrylic acid) copolymers. Macromolecules 40, 6564–6571 (2007).

    Article  Google Scholar 

  9. 9.

    Trigg, E. B., Stevens, M. J. & Winey, K. I. Chain folding produces a multilayered morphology in a precise polymer: simulations and experiments. J. Am. Chem. Soc. 139, 3747–3755 (2017).

    Article  Google Scholar 

  10. 10.

    Trigg, E. B., Middleton, L. R., Moed, D. E. & Winey, K. I. Transverse orientation of acid layers in the crystallites of a precise polymer. Macromolecules 50, 8988–8995 (2017).

    Article  Google Scholar 

  11. 11.

    Mandal, J., Krishna Prasad, S., Rao, D. S. S. & Ramakrishnan, S. Periodically clickable polyesters: study of intrachain self-segregation induced folding, crystallization, and mesophase formation. J. Am. Chem. Soc. 136, 2538–2545 (2014).

    Article  Google Scholar 

  12. 12.

    Gierke, T. D., Munn, G. E. & Wilson, F. C. The morphology in nafion perfluorinated membrane products, as determined by wide- and small- angle X-ray studies. J. Polym. Sci. Polym. Phys. Ed. 19, 1687–1704 (1981).

    Article  Google Scholar 

  13. 13.

    Eisenberg, A. Clustering of ions in organic polymers. A theoretical approach. Macromolecules 3, 147–154 (1970).

    Article  Google Scholar 

  14. 14.

    Diat, O. & Gebel, G. Fuel cells: proton channels. Nat. Mater. 7, 13–14 (2008).

    Article  Google Scholar 

  15. 15.

    Kreuer, K. D. & Portale, G. A critical revision of the nano-morphology of proton conducting ionomers and polyelectrolytes for fuel cell applications. Adv. Funct. Mater. 23, 5390–5397 (2013).

    Article  Google Scholar 

  16. 16.

    Mauritz, K. A. & Moore, R. B. State of Understanding of Nafion. Chem. Rev. 104, 4535–4585 (2004).

    Article  Google Scholar 

  17. 17.

    Kusoglu, A., Mosdestino, M. A., Hexemer, A., Segalman, R. A. & Weber, A. Z. Subsecond morphological changes in Nafion during water uptake detected by small-angle X-ray scattering. ACS Macro Lett. 1, 33–36 (2012).

    Article  Google Scholar 

  18. 18.

    Kreuer, K. D. Ion conducting membranes for fuel cells and other electrochemical devices. Chem. Mater. 26, 361–380 (2013).

    Article  Google Scholar 

  19. 19.

    Rubatat, L., Rollet, A. L., Gebel, G. & Diat, O. Evidence of elongated polymeric aggregates in Nafion. Macromolecules 35, 4050–4055 (2002).

    Article  Google Scholar 

  20. 20.

    Schmidt-rohr, K. & Chen, Q. Parallel cylindrical water nanochannels in Nafion fuel-cell membranes. Nat. Mater. 7, 75–83 (2008).

    Article  Google Scholar 

  21. 21.

    Li, N. & Guiver, M. D. Ion transport by nanochannels in ion-containing aromatic copolymers. Macromolecules 47, 2175–2198 (2014).

    Article  Google Scholar 

  22. 22.

    Vetter, S., Ruffmann, B., Buder, I. & Nunes, S. P. Proton conductive membranes of sulfonated poly(ether ketone ketone). J. Memb. Sci. 260, 181–186 (2005).

    Article  Google Scholar 

  23. 23.

    Fujimoto, C. H., Hickner, M. A., Cornelius, C. J. & Loy, D. A. Ionomeric poly(phenylene) prepared by Diels-Alder polymerization: synthesis and physical properties of a novel polyelectrolyte. Macromolecules 38, 5010–5016 (2005).

    Article  Google Scholar 

  24. 24.

    Elabd, Y. A. & Hickner, M. A. Block copolymers for fuel cells. Macromolecules 44, 1–11 (2011).

    Article  Google Scholar 

  25. 25.

    Elabd, Y. A., Napadensky, E., Walker, C. W. & Winey, K. I. Transport properties of sulfonated poly(styrene-b-isobutylene-b-styrene) triblock copolymers at high ion-exchange capacities. Macromolecules 39, 399–407 (2006).

    Article  Google Scholar 

  26. 26.

    Kim, H. K., Zhang, M., Yuan, X., Lvov, S. N. & Chung, T. C. M. Synthesis of polyethylene-based proton exchange membranes containing PE backbone and sulfonated poly(arylene ether sulfone) side chains for fuel cell applications. Macromolecules 45, 2460–2470 (2012).

    Article  Google Scholar 

  27. 27.

    Nakabayashi, K., Higashihara, T. & Ueda, M. Polymer electrolyte membranes based on cross-linked highly sulfonated multiblock copoly(ether sulfone)s. Macromolecules 43, 5756–5761 (2010).

    Article  Google Scholar 

  28. 28.

    Miyanishi, S., Fukushima, T. & Yamaguchi, T. Synthesis and property of semicrystalline anion exchange membrane with well-defined ion channel structure. Macromolecules 48, 2576–2584 (2015).

    Article  Google Scholar 

  29. 29.

    Gadjourova, Z., Andreev, Y. G., Tunstall, D. P. & Bruce, P. G. Ionic conductivity in crystalline polymer electrolytes. Nature 412, 520–523 (2001).

    Article  Google Scholar 

  30. 30.

    Cheng, S., Smith, D. M. & Li, C. Y. How does nanoscale crystalline structure affect ion transport in solid polymer electrolytes? Macromolecules 47, 3978–3986 (2014).

    Article  Google Scholar 

  31. 31.

    Schulz, M. D., Sauty, N. F. & Wagener, K. B. Morphology control in precision polyolefins. Appl. Petrochem. Res. 5, 3–8 (2015).

    Article  Google Scholar 

  32. 32.

    Buitrago, C. F. et al. Room temperature morphologies of precise acid- and ion-containing polyethylenes. Macromolecules 46, 9003–9012 (2013).

    Article  Google Scholar 

  33. 33.

    Middleton, L. R. et al. Hierarchical acrylic acid aggregate morphologies produce strain-hardening in precise polyethylene-based copolymers. Macromolecules 48, 3713–3724 (2015).

    Article  Google Scholar 

  34. 34.

    Seitz, M. E. et al. Nanoscale morphology in precisely sequenced poly(ethylene-co-acrylic acid) zinc ionomers. J. Am. Chem. Soc. 132, 8165–8174 (2010).

    Article  Google Scholar 

  35. 35.

    Gaines, T. W., Bell, M.H., Trigg, E. B., Winey, K. I. & Wagener, K. B. Precision sulfonic acid polyolefins via heterogenous to homogenous deprotection. Macromol. Chem. Phys. (2018).

  36. 36.

    Kreuer, K. D., Paddison, S. J., Spohr, E. & Schuster, M. Transport in proton conductors for fuel cell applications: simulation, elementary reactions and phenomenology. Chem. Rev. 104, 4637–4678 (2004).

    Article  Google Scholar 

  37. 37.

    Feng, S. & Voth, G. A. Proton solvation and transport in hydrated Nafion. J. Phys. Chem. B 115, 5903–5912 (2011).

    Article  Google Scholar 

  38. 38.

    Choi, P., Jalani, N. H. & Datta, R. Thermodynamics and proton transport in Nafion. J. Electrochem. Soc. 152, E123–E130 (2005).

    Article  Google Scholar 

  39. 39.

    Suarez, S. N., Jayakody, J. R. P., Greenbaum, S. G., Zawodzinski, T. & Fontanella, J. J. A fundamental study of the transport properties of aqueous superacid solutions. J. Phys. Chem. B 114, 8941–8947 (2010).

    Article  Google Scholar 

  40. 40.

    Urata, S. et al. Molecular dynamics simulation of swollen membrane of perfluorinated ionomer. J. Phys. Chem. B 109, 4269–4278 (2005).

    Article  Google Scholar 

  41. 41.

    Lane, J. M. D., Chandross, M., Stevens, M. J. & Grest, G. S. Water in nanoconfinement between hydrophilic self-assembled monolayers. Langmuir 24, 5209–5212 (2008).

    Article  Google Scholar 

  42. 42.

    Leng, Y. & Cummings, P. T. Fluidity of hydration layers nanoconfined between mica surfaces. Phys. Rev. Lett. 94, 19–22 (2005).

    Google Scholar 

  43. 43.

    Savage, J. & Voth, G. A. Persistent subdiffusive proton transport in perfluorosulfonic acid membranes. J. Phys. Chem. Lett. 5, 3037–3042 (2014).

    Article  Google Scholar 

  44. 44.

    Perrin, J., Lyonnard, S., Guillermo, A. & Levitz, P. Water dynamics in ionomer membranes by field-cycling NMR relaxometry. J. Phys. Chem. B 110, 5439–5444 (2006).

    Article  Google Scholar 

  45. 45.

    Jankowska, A., Zalewska, A., Skalska, A., Ostrowski, A. & Kowalak, S. Proton conductivity of imidazole entrapped in microporous molecular sieves. Chem. Commun. 53, 2475–2478 (2017).

    Article  Google Scholar 

  46. 46.

    Trigg, E. B., Tiegs, B. J., Coates, W. & Winey, K. I. High morphological order in a nearly precise acid-containing polymer and ionomer. ACS Macro Lett. 6, 947–951 (2017).

    Article  Google Scholar 

  47. 47.

    Zawodzinski, T. A. et al. Water uptake by and transport through Nafion 117 membranes. J. Electrochem. Soc. 140, 1041–1047 (1993).

    Article  Google Scholar 

  48. 48.

    Yin, Y. et al. Synthesis, proton conductivity and methanol permeability of a novel sulfonated polyimide from 3-(2′,4′-diaminophenoxy)propane sulfonic acid. Polymer 44, 4509–4518 (2003).

    Article  Google Scholar 

  49. 49.

    Abbott, L. J. & Frischknecht, A. L. Nanoscale structure and morphology of sulfonated polyphenylenes via atomistic simulations. Macromolecules 50, 1184–1192 (2017).

    Article  Google Scholar 

  50. 50.

    Gaines, T. W. Oxidized Sulfur Functionalized Polymers via ADMET Polymerization. PhD thesis, Univ. Florida (2015).

  51. 51.

    Gaines, T. W. & Wagener, K. B. Sulfonated polyethylene. US patent 9,724,686 (2017).

  52. 52.

    Salas-De La Cruz, D. et al. Environmental chamber for in situ dynamic control of temperature and relative humidity during X-ray scattering. Rev. Sci. Instrum. 83, 025112 (2012).

    Article  Google Scholar 

  53. 53.

    Heiney, P. Datasqueeze: a software tool for powder and small-angle X-ray diffraction analysis. Comm. Powder Diffr. Newsl. 32, 9–11 (2005).

    Google Scholar 

  54. 54.

    Abràmoff, M. D., Magalhães, P. J. & Ram, S. J. Image processing with ImageJ. Biophoton. Int. 11, 36–41 (2004).

    Google Scholar 

  55. 55.

    Plimpton, S. Fast parallel algorithms for short-range molecular dynamics. J. Comput. Phys. 117, 1–19 (1995).

    Article  Google Scholar 

  56. 56.

    Siu, S. W. I., Pluhackova, K. & Böckmann, R. A. Optimization of the OPLS-AA force field for long hydrocarbons. J. Chem. Theory Comput. 8, 1459–1470 (2012).

    Article  Google Scholar 

  57. 57.

    Middleton, L. R. et al. Heterogeneous chain dynamics and aggregate lifetimes in precise acid-containing polyethylenes: experiments and simulations. Macromolecules 49, 9176–9185 (2016).

    Article  Google Scholar 

  58. 58.

    Canongia Lopes, J. N., Pádua, A. A. H. & Shimizu, K. Molecular force field for ionic liquids IV: trialkylimidazolium and alkoxycarbonyl-imidazolium cations; alkylsulfonate and alkylsulfate anions. J. Phys. Chem. B 112, 5039–5046 (2008).

    Article  Google Scholar 

  59. 59.

    Price, D. J. & Brooks, C. L. A modified TIP3P water potential for simulation with Ewald summation. J. Chem. Phys. 121, 10096–10103 (2004).

    Article  Google Scholar 

  60. 60.

    Baaden, M., Burgard, M. & Wipff, G. TBP at the water−oil interface: the effect of TBP concentration and water acidity investigated by molecular dynamics simulations. J. Phys. Chem. B 105, 11131–11141 (2001).

    Article  Google Scholar 

  61. 61.

    Hockney, R. W. & Eastwood, J. W. Computer Simulation Using Particles (Taylor & Francis, New York, NY, 1988).

  62. 62.

    Bolintineanu, D. S., Stevens, M. J. & Frischknecht, A. L. Atomistic simulations predict a surprising variety of morphologies in precise ionomers. ACS Macro Lett. 2, 206–210 (2013).

    Article  Google Scholar 

  63. 63.

    Lueth, C. A., Bolintineanu, D. S., Stevens, M. J. & Frischknecht, A. L. Hydrogen-bonded aggregates in precise acid copolymers. J. Chem. Phys. 140, 054902 (2014).

    Article  Google Scholar 

  64. 64.

    Bolintineanu, D. S., Stevens, M. J. & Frischknecht, A. L. Influence of cation type on ionic aggregates in precise ionomers. Macromolecules 46, 5381–5392 (2013).

    Article  Google Scholar 

  65. 65.

    Brubach, J. B. et al. Performance of the AILES THz-infrared beamline at SOLEIL for high resolution spectroscopy. AIP Conf. Proc. 1214, 81–84 (2010).

    Article  Google Scholar 

  66. 66.

    Roy, P., Rouzieres, M., Qi, Z. & Chubar, O. The AILES infrared beamline on the third generation synchrotron radiation facility SOLEIL. Infrared Phys. Technol. 49, 139–146 (2006).

    Article  Google Scholar 

  67. 67.

    Bernardina, S. D. et al. New experimental set-ups for studying nanoconfined water on the AILES beamline at SOLEIL. Vib. Spectrosc. 75, 154–161 (2014).

    Article  Google Scholar 

  68. 68.

    Voute, A. et al. New high-pressure/low-temperature set-up available at the AILES beamline. Vib. Spectrosc. 86, 17–23 (2016).

    Article  Google Scholar 

Download references


E.B.T and K.I.W. acknowledge funding from the National Science Foundation (NSF) DMR 1506726, NSF PIRE 1545884, and the Army Research Office W911NF1310363. T.W.G. and K.B.W. thank the National Science Foundation (DMR1505778) for partial financial support for this project. This material also is based on catalyst work supported by, or in part by, the Army Research Office under the grant W911NF1310362. E.B.T, M.M. and P.R. acknowledge support from the Centre national de la recherche scientifique (CNRS) at the laboratoire des Systèmes Moléculaires et nanoMatériaux pour l’Energie et la Santé in Grenoble, France (UMR5819-SyMMES (CNRS/CEA/Univ. Grenoble Alpes)), and funding from the Agence Nationale de le Recherche (ANR): ANR-15-PIRE-0001-01 and ANR-15-PIRE-0001-07. D.E.M. acknowledges funding from Rachleff Scholars Program of the University of Pennsylvania. This work was performed, in part, at the Center for Integrated Nanotechnologies, an Office of Science User Facility operated for the US Department of Energy (DOE) Office of Science. Sandia National Laboratories is a multimission laboratory managed and operated by National Technology and Engineering Solutions of Sandia, LLC, a wholly owned subsidiary of Honeywell International, Inc., for the US Department of Energy’s National Nuclear Security Administration under contract DE-NA-0003525. We acknowledge the Laboratory for Research on the Structure of Matter (LRSM), supported by NSF DMR 11-20901. We acknowledge support from the Army Research Office Defense University Research Instrumentation Program (ARO DURIP) grant W911NF-14-1-0466. We acknowledge the Synchrotron SOLEIL for beamtime and financial support, and J.-B. Brubach as a local contact on the AILES beamline for the infrared absorbance data at various humidities. We acknowledge H. Mendil-Jakani for assistance with preliminary X-ray scattering measurements and E. Dubard for experimental support. This research used resources of the Advanced Photon Source, a US DOE Office of Science User Facility operated for the DOE Office of Science by Argonne National Laboratory under contract no. DE-AC02-06CH11357. In particular we acknowledge E. Bailey and S. Narayanan of beamline 8-ID-I for the small-angle X-ray scattering data presented in Supplementary Fig. 5. We thank A. Frischknecht (Sandia National Laboratories), A. Patel (University of Pennsylvania) and L. Gonon (UMR5819-SyMMES (CNRS/CEA/Univ. Grenoble Alpes)) for helpful discussions. We thank Materia Inc. for their generous donation of the catalyst used in this project. We thank C. Lee-Georgescu for illustrating Figs. 1b, 2c,d and 4a–c.

Author information




E.B.T. and K.I.W. generated the main ideas of the project, measured X-ray scattering, conductivity and sorption, performed simulations, analysed all data and wrote most of the text of this paper. T.W.G. and K.B.W. conceived of and carried out the synthesis of the polymer. M.M. and P.R. contributed ideas and interpretation and edited the text. M.M. collected infrared absorbance data and sorption data. D.E.M. collected conductivity data. M.J.S. contributed simulation expertise, ideas and interpretation, and edited the text.

Corresponding author

Correspondence to Karen I. Winey.

Ethics declarations

Competing interests

The authors declare no competing interests.

Additional information

Publisher’s note: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Supplementary information

Supplementary Information

Supplementary Figures 1–12, Supplementary Table 1, Supplementary References 1–2

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Trigg, E.B., Gaines, T.W., Maréchal, M. et al. Self-assembled highly ordered acid layers in precisely sulfonated polyethylene produce efficient proton transport. Nature Mater 17, 725–731 (2018).

Download citation

Further reading


Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing