Dielectric properties of cross-linked poly(ethylene oxide) (PEO) with different mesh sizes, doped with lithium salt lithium bis(trifluoromethanesulfonyl)imide (LiTFSI), have been studied in frequency region between 0.1 and 107 Hz and in broad temperature range. Results were compared with linear PEO of 1000 g/mol. Dielectric responses of the systems are dependent on frequency and thermally activated. Systems exhibit different responses in semi-crystalline and molten state. Increase of temperature promotes polarization; whereas, increase of frequency lessens it. In other words, polarization is thermally activated and local conductivity reduced. Generally, one observes enhanced dc conductivity in linear PEO as compared to cross-linked PEO at high temperature and the opposite at low temperature. Resonance responses are observed in low-molecular cross-linked PEO and in linear PEO at low temperature. These responses lead to splitting of polarization relaxation at frequencies beyond low-frequency range. Salt-comprising systems display only relaxation-type dielectric response. Imaginary parts of response spectra show distribution of relaxation times. It turns out that this distribution is independent of temperature in the low-frequency range, but depends on concentration of salt in the cross-linked polymer. In both systems, neat cross-linked and linear polymer of low-molecular mass, one observes coexistence of non-local and local motions of charged entities even at very low temperature.
Linear and cross-linked PEO Polymer electrolyte with LiTFSI Impedance spectra
This is a preview of subscription content, log in to check access.
The presentation, analysis, and discussion of impedance spectra are based on data provided by Professor J. Kressler and his students, Martin-Luther University Halle-Wittenberg, Germany. The author expresses his thanks for collecting and granting of the data.
Shen M, Lin Y, Li M, Nan CW (2007) High dielectric performance of polymer composite films induced by a percolating inter-particle barrier. Adv Mater 19:1418–1422CrossRefGoogle Scholar
Smith RC, Liang C, Landry M, Nelson JK, Schadler LS (2008) The mechanism leading to useful electric properties of polymer dielectrics. IEEE Dielct El In 15:187–196CrossRefGoogle Scholar
Lin W, Song MS, Kong B, Cui Y (2017) Flexible and stretchable energy storage: advances and future perspectives. Adv Mater 29(1-34):1603436Google Scholar
Carvalho M, Guegan P, Cheradame H, Gomes AS (2000) Variation of the mesh size of PEO-based networks filled with TFSILi: from an Arrhenius to WLF type conductivity behavior. Eur Polym J 36:401–409CrossRefGoogle Scholar
Samiullah MH, Reichert D, Zinkevich T, Kressler J (2013) NMR characterization of PEG networks synthsized by CuAAC using reactive oligomers. Macromolecules 46:6922–6930CrossRefGoogle Scholar
Pulst M, Kressler J (2014) Characterization of linear and cross-linked poly(ethylene oxide), MSc Thesis M. Pulst, Martin-Luther University Halle-Wittenberg, Halle, GermanyGoogle Scholar
Fetters LF, Lohse DJ, Millner ST, Grasley WW (1999) Packing length in linear polymer melts on the entanglement. Macromolecules 32:6847–6851CrossRefGoogle Scholar
Nazmul H (2016) Master thesis, Martin-Luther-University, Halle/SaaleGoogle Scholar
Cheng S, Smith DM, Li CY (2015) Anisotropic ion transport in poly(ethylene oxide)/LiClO4 solid state electrolyte tempered by grapheme oxide. Macromolecules 48:4503–4510CrossRefGoogle Scholar
Cheng S, Smith DM, Pan QW, Wang SJ, Li CY (2015) Anisotropic ion transport in nano-structured solid polymer electrolytes. RSC Adv 5:48793–48810CrossRefGoogle Scholar
Debye P (1929) Polar Molecules. Chemical Catalog Company, New York reprinted by Dover Publishers New York, 1945Google Scholar
Liang YH, Wang CC, Chen CY (2008) Synthesis and characterization of a new network polymer electrolyte containing polyether in the main chains and side chains. Eur Polym J 44:2376–2384CrossRefGoogle Scholar
Brandrup J, Immergut EH, Eds (1989) Polymer handbook 3rd ed., PEO. Wiley Interscience, New York, p 545Google Scholar
Walter R, Selser JC, Smith M, Bogoslovov R, Piet G (2002) Network viscoelastic behavior in poly(ethylene oxide) melts: effects of temperature and dissolved LiClO4 on network structure and dynamic behavior. J Chem Phys 117:427–440CrossRefGoogle Scholar