Recent Advances in Innovative Polymer Electrolytes based on Poly(ionic liquid)s

Single-Ion Block Copoly(ionic liquid)s as Electrolytes for All-Solid State Lithium Batteries

Polymer electrolytes have been proposed as replacement for conventional liquid electrolytes in lithium-ion batteries (LIBs) due to their intrinsic enhanced safety. Nevertheless, the power delivery of these materials is limited by the concentration gradient of the lithium salt. Single-ion conducting polyelectrolytes represent the ideal solution since their nature prevents polarization phenomena. Herein, the preparation of a new family of single-ion conducting block copolymer polyelectrolytes via reversible addition-fragmentation chain transfer polymerization technique is reported. These copolymers comprise poly(lithium 1-[3-(methacryloyloxy)propylsulfonyl]-1-(trifluoromethylsulfonyl)imide) and poly(ethylene glycol) methyl ether methacrylate blocks. The obtained polyelectrolytes show low Tg values in the range of -61 to 0.6 °C, comparatively high ionic conductivity (up to 2.3 × 10(-6) and 1.2 × 10(-5) S cm(-1) at 25 and 55 °C, respectively), wide electrochemical stability (up to 4.5 V versus Li(+)/Li), and a lithium-ion transference number close to unity (0.83). Owing to the combination of all mentioned properties, the prepared polymer materials were used as solid polyelectrolytes and as binders in the elaboration of lithium-metal battery prototypes with high charge/discharge efficiency and excellent specific capacity (up to 130 mAh g(-1)) at C/15 rate.

Synthesis of Monodisperse Silica Particles Grafted with Concentrated Ionic Liquid-Type Polymer Brushes by Surface-Initiated Atom Transfer Radical Polymerization for Use as a Solid State Polymer Electrolyte

A polymerizable ionic liquid, N,N-diethyl-N-(2-methacryloylethyl)-N-methylammonium bis(trifluoromethylsulfonyl)imide (DEMM-TFSI), was polymerized via copper-mediated atom transfer radical polymerization (ATRP). The polymerization proceeded in a living manner producing well-defined poly(DEMM-TFSI) of target molecular weight up to about 400 K (including a polycation and an counter anion). The accurate molecular weight as determined by a GPC analysis combined with a light scattering measurement, and the molecular weight values obtained exhibited good agreement with the theoretical values calculated from the initial molar ratio of DEMM-TFSI and the monomer conversion. Surface-initiated ATRP on the surface of monodisperse silica particles (SiPs) with various diameters was successfully performed, producing SiPs grafted with well-defined poly(DEMM-TFSI) with a graft density as high as 0.15 chains/nm². Since the composite film made from the silica-particle-decorated polymer brush and ionic liquid shows a relatively high ionic conductivity, we have evaluated the relationship between the grafted brush chain length and the ionic conductivity.

Synthesis and characterization of responsive poly(anionic liquid) microgels

Responsive poly(anionic liquid) microgels are synthesized by polymerization of tetrabutylphosphonium 4-styrenesulfonate, which can be further functionalized to harness catalytic properties.

Poly(ionic liquid)s with controlled architectures and their use in the making of ionogels with high conductivity and tunable rheological properties

We describe the preparation as well as the electrochemical and mechanical properties of a series of novel well-defined poly(ionic liquids) (PILs) featuring a finely tuned cross-linking ratio.

Poly(1,2,3-triazolium)s: a new class of functional polymer electrolytes

Poly(1,2,3-triazolium)s are tunable and highly functional ion conducting materials that stretch out the actual boundaries of PILs macromolecular design.

Polymerized imidazolium ionic liquids crosslinking sulfonated poly(ether ether ketone) (SPEEK) for high-temperature proton exchange membrane

An ionic liquid (IL) monomer of (acryloyloxy)propanylimidazolium chloride with unsaturated carbon–carbon double bonds was synthesized.

Biosourced 1,2,3-triazolium ionic liquids derived from isosorbide

The drastic influence of 1,4-3,6-dianhydrohexitols stereochemistry on physical, thermal and ion conducting properties.

Turning into poly(ionic liquid)s as a tool for polyimide modification: synthesis, characterization and CO2 separation properties

A synthetic method for the transformation of polyimides into poly(ionic liquid)s with improved properties is suggested.

Synthesis and conductivity of hyperbranched poly(triazolium)s with various end-capping groups

Hyperbranched poly(triazolium)s bearing different terminal groups were synthesized, and displayed an elevated conductivity upon the introduction of various flexible end-capped groups and the increase of temperature.

Adsorption Kinetics at Silica Gel/Ionic Liquid Solution Interface

A series of imidazolium and pyridinium ionic liquids with different anions (Cl(-), Br(-), BF₄(-), PF₆(-)) has been evaluated for their adsorption activity on silica gel. Quantification of the ionic liquids has been performed by the use of RP-HPLC with organic-aqueous eluents containing an acidic buffer and a chaotropic salt. Pseudo-second order kinetic models were applied to the experimental data in order to investigate the kinetics of the adsorption process. The experimental data showed good fitting with this model, confirmed by considerably high correlation coefficients. The adsorption kinetic parameters were determined and analyzed. The relative error between the calculated and experimental amount of ionic liquid adsorbed at equilibrium was within 7%. The effect of various factors such as initial ionic liquid concentration, temperature, kind of solvent, kind of ionic liquid anion and cation on adsorption efficiency were all examined in a lab-scale study. Consequently, silica gel showed better adsorptive characteristics for imidazolium-based ionic liquids with chaotropic anions from aqueous solutions in comparison to pyridinium ionic liquids. The adsorption was found to decrease with the addition of organic solvents (methanol, acetonitrile) but it was not sensitive to the change of temperature in the range of 5-40 °C.

Conducting, Self-Assembled, Nacre-Mimetic Polymer/Clay Nanocomposites

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.

A well-defined polyelectrolyte and its copolymers by reversible addition fragmentation chain transfer (RAFT) polymerization: synthesis and applications

Controlled polymerization and self-assembly of novel block copolymer electrolytes.

Unconventional poly(ionic liquid)s combining motionless main chain 1,2,3-triazolium cations and high ionic conductivity

We report the synthesis of poly(1,2,3-triazolium ionic liquid)s by the polyaddition of α-azide-ω-alkyne monomers with short n-hexyl and diethylene glycol spacers by both copper(I)-catalyzed and thermal Huisgen azide–alkyne 1,3-dipolar cycloaddition.

Poly(ionic liquid)s as phase splitting promoters in aqueous biphasic systems

The ability of hydrophilic pyrrolidinium-based PILs to promote phase splitting in aqueous solutions of K₃PO₄ is disclosed in this work for the first time.

Synthesis and characterization of glycidyl-polymer-based poly(ionic liquid)s: highly designable polyelectrolytes with a poly(ethylene glycol) main chain

Glycidyl-polymer-based poly(ionic liquid)s with different spacers and ionic moieties were synthesized by click functionalization of a glycidyl azide polymer.

Triethylene glycol-based poly(1,2,3-triazolium acrylate)s with enhanced ionic conductivity

A well-defined triethylene glycol-based poly(1,2,3-triazolium acrylate) having a bis(trifluoromethane)sulfonimide anion and an anhydrous ionic conductivity of 10⁻⁵ S cm⁻¹ at 30 °C is reported.