Three novel ionic monomers having highly delocalized anions and electrochemically stable mobile cations, namely, 1-butyl-1-methylpyrrolidiniumpropylsulfonyl)]methanide and 1-butyl-1-methylpyrrolidinium 1-cyano-1- [(3-(methacryloyloxy) propylsulfonyl)]imide were synthesized and characterized. The structure of these monomers was designed to be a mimic of the most highly conductive bis(trifluoromethylsulfonyl)imide, tricyanomethanide and dicyanamide anions. By radical polymerization procedure a series of new anionic ''polymeric ionic liquids'' (PILs) were prepared. The solubility of these linear PILs, thermal stability, glass transition temperatures, molar masses and ionic conductivities were estimated. An advantage of the novel PILs was demonstrated by the comparison of their ionic conductivity at 25 C (2.0 Â 10 À8 O 1.6 Â 10 À7 S cm À1 ) with the unmodified poly(1-ethyl-1-methylpyrrolidinium 3-(methacryloyloxy)propane-1-sulfonate) analog. The increase in ionic conductivity is as high as three orders of magnitude and was found to depend on the size of the attached anion. The new ionic monomers were subsequently copolymerized with poly(ethylene glycol) dimethacrylate and poly (ethylene glycol) methyl ether methacrylate. The investigation of the copolymers properties revealed further improvement of the conductivity in approximately two orders of magnitude and the achievement of s ¼ 4.8 O 6.8 Â 10 À6 S cm À1 ) at 40 C.

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The achievement of high ionic conductivity in new "polymeric ionic liquids" (PILs) is of great interest as it refers to the solid state electrolytes and their applications in electrochemistry. Four ionic monomers, including two new ones, namely N-[(2-methacryloyloxy)-propyl]-N-methylpyrrolidinium bis(trifluoromethylsulfonyl)amide (M1), 1-[2-(methacryloyloxy)propyl]-3-methylimidazolium bis(trifluoromethylsulfonyl)amide (M2), N-methyl-N-ethylpyrrolidinium(3-sulfopropyl) methacrylate (M3), and 1-methyl-3-ethylimidazolium(3-sulfopropyl) methacrylate (M4), were prepared and used both for the synthesis of linear PILs and ionic networks with poly(ethylene glycol) dimethacrylate (PEGDM). The optimal polymerization conditions for obtaining high molar mass PILs (M sD up to 1.24 Â 10 6 g/mol) were identified. The copolymerization of oppositely charged monomers was studied as well. Polycations, polyanions, and their random ionic copolymers were compared in terms of their physical properties. The examined properties were found to depend mainly on the nature of the counterion. It became obvious that the bulk ionic conductivity of hydrophilic polyanions is greatly affected by the humidity. It increases up to 220 times upon transferring from dry air to 20% relative humidity. Ionic conductivity increased in random ionic copolymers synthesized from oppositely charged monomers feasibly, suggesting that the ion transport was improved by the partial formation of mobile ionic liquid within the polymer.

Various 1,3‐dialkylimidazolium and tetraalkylphosphonium ionic liquids (ILs), including novel ones, have been studied as reaction media for free radical polymerization of methyl methacrylate (MMA), acrylonitrile (AN) and 1‐vinyl‐3‐ethylimidazolium salts (ViEtIm+)Y−. The influence of IL's nature upon the polymer formulation was investigated. The use of different ionic liquids allows not only to obtain the polymers with high molecular weight (PMMA, ${\bar M}_w$ up to 5,770,000 g/mol; PAN, ${\bar M}_v$ up to 735,000 g/mol and poly[(ViEtIm+)Y−], $\bar M_z$ up to 1,130,000 g/mol) in high yields, but also to control the polymerization rate and molecular mass. The physicochemical characteristics, including mechanical properties, thermal stability and heat‐resistance of the obtained polymers were studied in order to compare with those of polymers prepared in a traditional media. It was found that elongation, tensile modulus and strength of PAN, which was synthesized in ionic liquid, are reliatively higher. The influence of IL's nature upon their ionic conductivity and the formation of conductive polymers from molten‐salt‐type vinyl monomers was investigated. Molecular design of the polymers simultaneously with the influence of IL's nature in order to achieve higher ionic conductivity is discussed. Flexible, transparent polymer films, obtained in different ways, show relatively high ionic conductivity (of about 10−5 S cm−1 at 20°C). Copyright © 2006 John Wiley & Sons, Ltd.

The cyclopolymerization of polar, ionic N,N-dibutyl-N,N-dipropargylammonium bis(trifluoromethylsulfonyl)imide (M1), N,N-dimethyl-N,N-dipropargylammonium bis(trifluoromethylsulfonyl)imide (M2), N,N-dipropargylmorpholinium bis(trifluoromethylsulfonyl)imide (M3), and N-propyl-N,N-dipropargylamine (M4) using five different well-defined Schrock- and trifluoroacetate-modified Grubbs-type initiators was investigated. Ru-based initiators allowed for the polymerization of M1−M3 with average isolated polymer yields around 25−40%, however, poly-M2 and poly-M3 thus prepared consisted >95% of five-membered ring structures, i.e., (3,4-(1H-2,5-dihydropyrrolylene)vinylene)s units. In contrast, the use of the Schrock type initiator Mo(N-2,6-iPr2C6H3)(CHMe2Ph)(OC(CH3)(CF3)2)2 allowed for quantitative polymer yields, whereas, poly-M2 prepared by the action of this initiator was based on both five- and six-membered, i.e., (3,5-(1,2,5,6-tetrahydropyridinylene)methylidene) cyclic units. Polymers were synthesized with molecular weights M n < 21 800 g/mol and polydispersity indices in the range of 1.04 < PDI < 1.37 and 1.01 < PDI < 1.08 with Ru- and Mo-based initiators, respectively. They were additionally investigated for their thermal stability and ionic conductivity. Finally, the solvatochromic behavior of the polymers prepared was studied. Particularly, solutions of poly-M1 prepared by the action of Ru-based initiators displayed a high sensitivity toward traces of water in N,N-dimethylformamide.

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Poly(norbornene)s with pendant imidazolium moieties and three different counter anions, i.e. poly[exo,endo‐5‐norbornene‐2‐yl‐carboxyethyl‐3‐ethylimidazolium bis(trifluoromethyl‐sulfonyl)imide], poly(exo,endo‐5‐norbornene‐2‐yl‐carboxyethyl‐3‐ethylimidazolium tetrafluoroborate), and poly(exo,endo‐5‐norbornene‐2‐yl‐carboxyethyl‐3‐ethylimidazolium hexafluorophosphate) were prepared via ROMP using ionic liquids as the reaction medium. The ionic polymers possessed $\overline M _{\rm w}$ in the range 8.1–44 × 103 and ionic conductivity up to 1.13 × 10−5 and 1.44 × 10−4 S · cm−1 at 20 and 50 °C, respectively. The solubility of the new polymeric ionic liquids, their thermal stability and their glass transition temperatures were investigated in detail. Ionic conductivities were found to depend on the nature of the counter‐anion and on the polymers' glass transition temperature rather than its molecular weight.magnified image

The main objective of this study was to replace the traditionally used hydrolytically unstable PF 6 and BF 4 ionic solvents with new, stable ionic liquids (ILs) and to investigate the potential of ILs in formulation of the polymers based on methyl methacrylate and acrylonitrile with narrow polydispersities, high yields and molecular weights. Various ILs with four anions, namely, tris(pentafluoroethyl)trifluorophosphate, trifluoromethanesulfonate, trifluoroacetate and tetracyanoborate, were tested. The influence of the IL's characteristics on the free radical polymerization process was found to be significant. Trifluoromethanesulfonate-and trifluoroacetate-based ionic solvents provide the formation of polymers with the highest molecular weight (M r E8.8Â10 5 for polyacrylonitrile (PAN) and M w E18.9Â10 5 for polymethylmethacrylate (PMMA)) in quantitative yield (PAN, 96%; PMMA, 92%). Taking into account, the high ionic conductivity and satisfactory electrochemical stability of the tetracyanoborate-based ILs, composite films derived from PAN and B(CN) 4 ILs were prepared and their physico-chemical properties were investigated. The nature of the cation strongly influences the properties of the resulting composite films, namely, their flexibility, transparency, surface morphology and ionic conductivity (the maximum conductivity was found to be 1.0Â10 À2 S cm À1 at 25 1C).