In the present study, polymerizable ionic liquids (ILs), 1-[n-(methacryloyloxy)alkyl]-3-methylimidazolium bromides (n = 2, 6, 7, or 10), were synthesized in high yields. Moreover, the compounds obtained (n = 6, 7, or 10) were used in the preparation of composite materials comprising a polymerized IL matrix and a nonpolymerizable IL additive, 1-ethyl-3-methylimidazolium tetrafluoroborate ([EMIM][BF4]) in various proportions (up to 75% vol/vol of [EMIM][BF4]). The UV-radiation-initiated photopolymerization process was monitored in situ by measuring the resistivities of the mixtures. An increase in [EMIM][BF4] content in the composites led to an increase in the ionic conductivities of the materials while retaining their solid state at levels as high as 40% vol/vol of the [EMIM][BF4] content. The 40% vol/vol composites had conductivities of approximately 10−4 S/cm compared to the conductivities of 10−5 S/cm for the corresponding neat polymerized ILs. Above this [EMIM][BF4] content, the materials were sticky gels, and from 50% vol/vol onwards, entirely liquid.
This is a preview of subscription content, access via your institution.
Buy single article
Instant access to the full article PDF.
Tax calculation will be finalised during checkout.
Subscribe to journal
Immediate online access to all issues from 2019. Subscription will auto renew annually.
Tax calculation will be finalised during checkout.
B. Kirchner: Topics in Current Chemistry: Ionic Liquids, Vol. 290 (Springer, Heidelberg, Germany, 2010), p. 345.
M. Freemantle: An Introduction to Ionic Liquids (RSC Publishing, Cambridge, UK, 2010), p. 281.
P. Wasserscheid and T. Welton: Ionic Liquids in Synthesis (Wiley-VCH Verlag GmbH & Co., Weinheim, Germany, 2002), p. 364.
M. Galinski, A. Lewandowski, and I. Stepniak: Ionic liquids as electrolytes. Electrochim. Acta 51(26), 5567 (2006).
T. Fukushima, A. Kosaka, Y. Ishimura, T. Yamamoto, T. Takigawa, N. Ishii, and T. Aida: Molecular ordering of organic molten salts triggered by single-walled carbon nanotubes. Science 300(5628), 2072 (2003).
R.P. Swatloski, S.K. Spear, J.D. Holbrey, and R.D. Rogers: Dissolution of cellulose with ionic liquids. J. Am. Chem. Soc. 124(18), 4974 (2002).
H. Olivier-Bourbigou, L. Magna, and D. Morvan: Ionic liquids and catalysis: Recent progress to knowledge. Appl. Catal., A 373(1–2), 1 (2010).
J.L. Anderson, D.W. Armstrong, and G-T. Wei: Ionic liquids in analytical chemistry. Anal. Chem. 78(9), 2893 (2006).
M. Armand, F. Endres, D.R. MacFarlane, H. Ohno, and B. Scrosati: Ionic-liquid materials for the electrochemical challenges of the future. Nat. Mater. 8(8), 621 (2009).
Y-S. Ye, J. Rick, and B-J. Hwang: Ionic liquids polymer electrolytes. J. Mater. Chem. A 1(8), 2719 (2013).
T.P. Lodge: Materials science: A unique platform for materials design. Science 321(5885), 50 (2008).
J. Yuan and M. Antonietti: Poly(ionic liquid)s: Polymers expanding classical property profiles. Polymer 52(7), 1469 (2011).
H. Ohno and K. Ito: Room-temperature molten salt polymers as a matrix for fast ion conduction. Chem. Lett. 27(8), 751 (1998).
H. Ohno: Design of ion conductive polymers based on ionic liquids. Macromol. Symp. 249–250, 551 (2007).
D. Mecerreyes: Polymeric ionic liquids: Broadening the properties and applications of polyelectrolytes. Prog. Polym. Sci. 36(12), 1629 (2011).
J. Tang, H. Tang, W. Sun, M. Radosz, and Y. Shen: Low pressure CO2 sorption in ammonium-based poly(ionic liquid)s. Polymer 46(26), 12460 (2005).
R. Marcilla, J.A. Blazquez, R. Fernandez, H. Grande, J.A. Pomposo, and D. Mecerreyes: Synthesis of novel polycations using the chemistry of ionic liquids. Macromol. Chem. Phys. 206(2), 299 (2005).
W. Ogihara, S. Washiro, H. Nakajima, and H. Ohno: Effect of cation structure on the electrochemical and thermal properties of ion conductive polymers obtained from polymerizable ionic liquids. Electrochim. Acta 51(13), 2614 (2006).
N.V. Tsarevsky and K. Matyjaszewski: “Green” atom transfer radical polymerization: From process design to preparation of well-defined environmentally friendly polymeric materials. Chem. Rev. 107(6), 2270 (2007).
H. Mori, M. Yahagi, and T. Endo: RAFT polymerization of N-vinylimidazolium salts and synthesis of thermoresponsive ionic liquid block co-polymers. Macromolecules 42(21), 8082 (2009).
Y.S. Vygodskii, A.S. Shaplov, E.I. Lozinskaya, K.A. Lyssenko, D.G. Golovanov, I.A. Malyshkina, N.D. Gavrilova, and M.R. Buchmeiser: Conductive polymer electrolytes derived from poly(norbornene)s with pendant ionic imidazolium moieties. Macromol. Chem. Phys. 209(1), 40 (2008).
O. Green, S. Grubjesic, S. Lee, and M.A. Firestone: The design of polymeric ionic liquids for the preparation of functional materials. Polym. Rev. 49(4), 339 (2009).
O. Azzaroni, A.A. Brown, and W.T.S. Huck: Tuneable wettability by clicking counterions into polyelectrolyte brushed. Adv. Mater. 19(1), 151 (2007).
Q. Zhang, X. Lu, Y. Qiao, L. Zhang, D-L. Liu, W. Zhang, G-X. Han, and X-M. Song: Direct electrochemistry and electrocatalysis of hemoglobin immobilized in a polymeric ionic liquid film. Electroanalysis 22(9), 1000 (2010).
J. Tang, W. Sun, H. Tang, M. Radosz, and Y. Shen: Enhanced CO2 absorption of poly(ionic liquid)s. Macromolecules 38(6), 2037 (2005).
Q. Zhao and J.L. Anderson: Highly selective GC stationary phases consisting of binary mixtures of polymeric ionic liquids. J. Sep. Sci. 33(1), 79 (2010).
S. Washiro, M. Yoshizawa, H. Nakajima, and H. Ohno: Highly ion conductive flexible films composed of network polymers based on polymerizable ionic liquids. Polymer 45(5), 1577 (2004).
H. Ohno: Electrochemical Aspects of Ionic Liquids (John Wiley & Sons, Inc., New York, 2005), p. 392.
R. Marcilla, F. Alcaide, H. Sardon, J. A. Pomposo, C. Pozo-Gonzalo, and D. Mecerreyes: Tailor-made polymer electrolytes based upon ionic liquid and their application in-all plastic electrochromic devices. Electrochem. Commun. 8(3), 482 (2006).
N.S. Allen: Photoinitiators for UV and visible curing of coatings: Mechanisms and properties. J. Photochem. Photobiol., A 100(1–3), 101 (1996).
D. Barta, S. Seifert, and M.A. Firestone: The effect of cation structure on the mesophase architecture of self-assembled and polymerized imidazolium-based ionic liquids. Macromol. Chem. Phys. 208(13), 1416 (2007).
T. Nakashima, M. Sakashita, Y. Nonoguchi, and T. Kawai: Sensitized photopolymerization of an ionic liquid-based monomer by using CdTe nanocrystals. Macromolecules 40(18), 6540 (2007).
K. Põhako-Esko, T. Taaber, K. Saal, R. Lõhmus, I. Kink, and U. Mäeorg: New method for synthesis of methacrylate type polymerizable ionic liquids. Synth. Commun. 43(21), 2846 (2013).
S.K. Kang, W.S. Kim, and B.H. Moon: An effective method for the preparation of ω-bromoalkanols from α,ω-diols. Synthesis 1985(12), 1161 (1985).
S. Ding, H. Tang, M. Radosz, and Y. Shen: Atom transfer radical polymerization of ionic liquid 2-(1-butylimidazolium-3-yl)ethyl methacrylate tetrafluoroborate. J. Polym. Sci., Part A: Polym. Chem. 42(22), 5794 (2004).
H. Chen, J-H. Choi, D. Salas-de la Cruz, K.I. Winey, and Y.A. Elabd: Polymerized ionic liquids: The effect of random co-polymer composition on ion conduction. Macromolecules 42(13), 4809 (2009).
S. Srinivasan, M.W. Lee, M.C. Grady, M. Soroush, and A.M. Rappe: Self-initiation mechanism in spontaneous thermal polymerization of ethyl and n-butyl acrylate: A theoretical study. J. Phys. Chem. A 114(30), 7975 (2010).
F.R. Mayo: Chain transfer in the polymerization of styrene. VIII. Chain transfer in bromobenzene and mechanism of thermal initiation. J. Am. Chem. Soc. 75, 6133 (1953).
V. Jovanovski, R. Marcilla, and D. Mecerreyes: Tuning the properties of functional pyrrolidinium polymers by co-polymerization of diallyldimethylammonium ionic liquids. Macromol. Rapid Commun. 31(18), 1646 (2010).
A. Jarosik, S.R. Krajewski, A. Lewandowski, and P. Radzimski: Conductivity of ionic liquids in mixtures. J. Mol. Liq. 123(1), 43 (2006).
H. Niedermeyer, J.P. Hallett, I.J. Villar-Garcia, P.A. Hunt, and T. Welton: Mixtures of ionic liquids. Chem. Soc. Rev. 41(23), 7780 (2012).
The authors would like to acknowledge the Estonian Science Foundation (Grant Nos. 8428 and 8794), Estonian Ministry of Education and Research (targeted Grant No. SF0180058s07), the European Regional Development Fund (Center of Excellence, Mesosystems: Theory and Applications, TK114; and “TRIBOFILM” 3.2.1101.12-0028), and the graduate school “Functional materials and technologies,” which received funding from the European Social Fund under Grant No. 1.2.0401.09-0079 in Estonia. The authors would like to acknowledge the NordForsk (Excellent Nordic Chemistry) for support. The authors also thank Silver Leinberg for his help with resistivity measurements.
About this article
Cite this article
Põhako-Esko, K., Timusk, M., Saal, K. et al. Increased conductivity of polymerized ionic liquids through the use of a nonpolymerizable ionic liquid additive. Journal of Materials Research 28, 3086–3093 (2013). https://doi.org/10.1557/jmr.2013.330