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The precision synthesis of poly(ionic liquid)s (PILs) in water is achieved for the first time by the cobalt-mediated radical polymerization (CMRP) of N-vinyl-3-alkylimidazolium-type monomers following two distinct protocols. The first involves the CMRP of various 1-vinyl-3-alkylimidazolium bromides conducted in water in the presence of an alkyl−cobalt(III) complex acting as a monocomponent initiator and mediating agent. Excellent control over molar mass and dispersity is achieved at 30°C. Polymerizations are complete in a few hours, and PIL chain-end fidelity is demonstrated up to high monomer conversions. The second route uses the commercially available bis(acetylacetonato)cobalt(II) (Co-(acac) 2 ) in conjunction with a simple hydroperoxide initiator (tertbutyl hydroperoxide) at 30, 40, and 50°C in water, facilitating the scaling-up of the technology. Both routes prove robust and straightforward, opening new perspectives onto the tailored synthesis of PILs under mild experimental conditions in water. P oly(ionic liquid)s (PILs) have emerged as a special class of polyelectrolyte materials, featuring tunable solubility, high ionic conductivity, and a broad range of glass transition temperatures. 1 Due to their specific properties emanating from the ionic liquid (IL) units and their intrinsic polymeric nature, PILs find potential applications in various areas, such as analytical chemistry, biotechnology, gas separation, dispersants, solid ionic conductors for energy, catalysis, etc. The main synthetic strategies for PILs include direct chain-growth polymerizationwhether controlled 2 or noncontrolled 3 of ionic liquid (IL) monomers, step-growth polymerization, 4 and postpolymerization modification of uncharged polymers by nitrogen quaternization. 5 Exchange of the counterion (anion or cation) is typically efficient, providing an additional method for the variation of PIL properties.In recent years, controlled radical polymerization (CRP) techniques have been applied to the synthesis of structurally well-defined PILs, with control attained over molar mass, dispersity, and end-group fidelity. Control of end-group functionality enables the precision engineering of IL-based block copolymers that possess unique self-assembly modes in solution 6 or in the bulk. 7 Confinement of PIL blocks within lamellar nanodomains of block copolymers has, for instance, led to polymer films with enhanced ionic conductivity. 7 The design of novel PIL structures is therefore necessary for the establishment of important structure/property relationships, required to expand the scope and realize the full potential of ILbased materials.The majority of studies has focused on the direct CRP of styrenic-or (meth)acrylic monomers containing pendant imidazolium groups, featuring various counteranions (e.g., Br − , BF 4 − , PF 6 − , and (CF 3 SO 2 ) 2 N − ). 2,8 In contrast, processes for CRP of N-vinyl-3-alkylimidazolium salts (VImX) are relatively underdeveloped due to difficulties in controlling the highly reactive growing polymer chains. Whil...

We demonstrate electrically and ionically conducting nacre-mimetic nanocomposites prepared using self-assembly of synthetic nanoclay in combination with PEDOT:PSS and a poly­(ionic liquid) polymer from aqueous dispersions. The resulting nacre-mimetics show high degrees of mesoscale order and combine high stiffness and high strength. In terms of conductivities, the resulting hybrids exceed simple additive behavior and display synergetic conductivities due to high levels of interfaces and anisotropic conductivity pathways. The approach highlights the integration of relevant functionalities into stiff and strong bioinspired materials, and shows that synergetic properties beyond mechanical performance can be realized in advanced multifunctional nanocomposites using nacre-inspired design principles.

Amphiphilic double poly(ionic liquid) (PIL) block copolymers are directly prepared by cobalt-mediated radical polymerization induced self-assembly (CMR-PISA) in water of N-vinyl imidazolium monomers carrying distinct alkyl chains. The cobalt-mediated radical polymerization of N-vinyl-3-ethyl imidazolium bromide (VEtImBr) is first carried out until high conversion in water at 30 °C, using an alkyl bis(acetylacetonate)cobalt(III) adduct as initiator and controlling agent. The as-obtained hydrophilic poly(N-vinyl-3-ethyl imidazolium bromide) (PVEtImBr) is then used as a macroinitiator for the CMR-PISA of N-vinyl-3-octyl imidazolium bromide (VOcImBr). Self-assembly of the amphiphilic PVEtImBr-b-PVOcImBr block copolymer, i.e., of PIL-b-PIL-type, rapidly takes place in water, forming polymer nanoparticles consisting of a hydrophilic PVEtImBr corona and a hydrophobic PVOcImBr core. Preliminary investigation into the effect of the size of the hydrophobic block on the dimension of the nanoparticles is also described.

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International audienceThe organometallic-mediated radical polymerization (OMRP) of N-vinyl-3-alkylimidazolium-type monomers, featuring the bis(trifluoromethylsulfonyl)imide counter-anion (Tf2N-) in the presence of Co(acac)(2) as controlling agent, is reported. Polymerizations of monomers with methyl, ethyl, and butyl substituents are fast, reaching high monomer conversion in ethyl acetate as solvent at 30 degrees C, and afford structurally well-defined hydrophobic poly(ionic liquid)s (PILs) of N-vinyl type. Block copolymer synthesis is also achieved by sequential OMRP of N-vinyl-3-alkyldazolium salts carrying different alkyl chains and different counteranions (Tf2N- or Br-). These block copolymerizations are carried out at 30 degrees C, either under homogeneous solution in methanol or in a biphasic medium consisting of a mixture of ethyl acetate and water. Unprecedented PIL-b-PIL block copolymers are thus prepared under these conditions. However, anion exchange occurs at the early stage of the growth of the second block. Finally, diblock copolymers generated in the biphasic medium can be readily coupled by addition of isoprene, forming all PIL-based and symmetrical ABA-type triblock copolymers in a one-pot process. Such a direct block copolymerization method, involving vinylimidazolium monomers bearing different alkyl chains, thus opens new opportunities in the precision synthesis of all PIL-based block copolymers of tunable properties

Combining the redox activity and remarkable adhesion propensity of polyphenols (such as catechol or pyrogallol) with the numerous tunable properties of poly(ionic liquid)s (PILs) is an attractive route to design inventive multifunctional macromolecular platforms. In this contribution, we describe the first synthesis of a novel family of structurally well-defined PILs functionalized with catechol/pyrogallol/phenol pendants by organometallic-mediated radical polymerization (OMRP) using an alkyl−cobalt(III) complex as initiator and mediating agent. The living character of the chains is also exploited to produce di-and triblock PILs, and the facile counteranion exchange reactions afforded a library of PILs-bearing free phenol/catechol/pyrogallol moieties. Electrochemical investigations of catechol/pyrogallolderived PILs in aqueous medium demonstrated the characteristic catechol to o-quinone transformations, whereas, quasireversible doping/undoping with supporting electrolyte cations (Li + /tetrabutylammonium + ) has been observed in organic media, suggesting a bright future for this new family of redox-active PILs as cathode material for secondary energy storage devices. Also, pendant catechol/pyrogallol groups mediated sustained anchoring onto the gold surface conferred PILs properties to the interface. As a proof-of-concept, both the adsorption and inhibition of proteins on polymer modified surfaces have been demonstrated in real time using the quartz crystal microbalance with dissipation technique. The exquisite physicochemical tunability of these innovative surface-and redox-active PILs makes them excellent candidates for a broad range of potential applications, including "smart surfaces" and electrochemical energy storage devices.

Novel organocobalt complexes featuring weak C-CoL2 bonds (L = acetylacetonate) are prepared and used as sources of halomethyl radicals. They permit the precision synthesis of α-halide functionalized and telechelic polymers in organic media or in water. Substitution of halide by azide allows derivatization of polymers using the CuAAC click reaction.