Polymeric Ionic Liquid Research Articles

Boosted electrochemical reduction detoxification and oxidation of clofibric acid by polymerized ionic liquid functionalized cathode: Parameter optimization and degradation mechanisms

The application of electrocatalytic degradation technology in the treatment of pharmaceuticals and personal care products (PPCPs) has attracted widespread attention currently. Through structure and properties characterization of catalysts we found that more uniformly distributed metal particles and excellent thermal stability were obtained by modification with poly(1-vinyl-3-butylimidazole hexafluorophosphate) ([(PV)BIM]PF6) on graphene to anchor the metal CoNi nanoparticles (CoNi/PILs-rGO). For assessing its application potential, the CoNi/PILs-rGO cathode in combination with Ti/RuO2/IrO2 anode to set up an experimental reaction system for the electrocatalytic degradation of clofibric acid (CA) simulated wastewater. Reactor settings for experimentation are optimized, and intermediates, alterations in toxicity during degradation, and active species are detected. The results of the single-factor experiment showed that the average removal rate of CA by the cathodic compartment was 97.18 % when the conditions were optimal. Two possible pathways of degradation are deduced from the CA intermediates, one is the C-Cl bond breaking in electrochemical reduction, and the other is that the C-O bond is directly broken by anodic reactive oxygen. Toxicity tests have shown that the anode produces some by-products that are more hazardous than the original chemical, while the cathode produces a dechlorination process that is ultimately more detoxifying.

Polymerizable Ionic Liquid-Derived N, S co-Doped sp3/sp2 Carbon as Electrocatalyst for H2O2 Generation.

The H2O2 generation via the green electrochemical process is of high interest. For the H2O2 electrochemical generation, the oxygen reduction reaction (ORR) is important. Unfortunately, the ORR is kinetically sluggish and catalysts are needed. However, noble metal ORR catalysts are pricy and scarcely applicable in applications. Therefore, non-precious metal catalysts are desired. Heteroatom-doped carbons show promise as metal-free ORR catalysts. The ORR catalytic activity will be enhanced by the carbon's sp2 and/or sp3 engineering. For N, S co-Cdoped and sp2/sp3 modulated carbon, a polymerizable ionic liquid of hydrolyzed vinyl imidazolium was studied. The carbon is studied as a metal-free catalyst for the ORR via the 2e- process. It is possible to get an onset potential of 0.88 V vs. RHE with approximately 50 % selectivity for the H2O2. The current study offers a simple technique for synthesizing heteroatom-doped sp2/sp3 designed carbon as catalysts for the electroreduction of O2 to produce H2O2, and a new way of tunning the sp3/sp2 carbon catalytic activity by modulating the ionic liquid.

Stability of Ionogels upon Contact with Water: Effect of Polymer Matrix Hydrophobicity and Ionic Liquid Solubility

Stability of Ionogels upon Contact with Water: Effect of Polymer Matrix Hydrophobicity and Ionic Liquid Solubility

Adsorption of phenolic compounds on polymeric ionic liquids: Adsorption isotherms interpretation and thermodynamic study

This study describes the thermodynamic assessment and steric interpretation of the 4-nitrophenol (4-NP) and 4-chlorophenol (4-CP) adsorption on polymeric ionic liquids (PILs) using advanced statistical physics model. A monolayer model with a single energy level was employed to elucidate the adsorption mechanisms of these phenolic compounds. The results showed that the orientation of 4-NP and 4-CP on the surface of this adsorbent was a combination of parallel and non-parallel configurations at the tested adsorption temperatures. The values of the adsorption capacities at saturation were 484.7 and 406.7 mg/g for4-NP and 4-CP, respectively. The modelling results indicated that more active sites from PILs surface were involved in the removal of 4-nitrophenol than those required for the 4-chlorophenol adsorption. The calculation of adsorption energies confirmed that the adsorption of 4-NP and 4-CP on PILs was exothermic and driven by physical forces involving hydrogen bonds and van der Waals forces. Three thermodynamic functions were analyzed to complete the macroscopic analysis of the adsorption mechanism for these relevant phenolic contaminants.

Preparation and evaluation of polymeric ionic liquid functionalized microparticles as the efficient adsorbent for pipette tip solid phase extraction of sulfonamides

Sulfonamides (SAs) residues are commonly found in environmental samples, which is highly concerning for public safety and environmental protection. The detection of SAs is quite important but challenging. In this work, a kind of polymeric ionic liquid functionalized microparticles (PIL-FM) was synthesized via a simple free radical polymerization reaction, and applied as the adsorbent for pipette tip solid phase extraction (PT-SPE) of three SAs from river water, milk powder and honey samples. The adsorption performance of PIL-FM on SAs were evaluated using adsorption kinetics and adsorption isotherms, and the results showed that PIL-FM had the best selectivity for SMZ with the maximum adsorption capacity was as high as 45.05 mg·g−1. The extraction process was optimized and the adsorption mechanism was preliminarily discussed. PIL-FM has the excellent selectivity for SAs mainly because of the strong π-π interaction, and the electrostatic repulsion between them in the elution step also has a positive impact. Under optimal conditions, combined with HPLC, this PT-SPE method had wide linearity (0.2–100 μg·L−1, R2 ≥ 0.9998) and low limits of detection (0.06–0.08 μg·L−1). The intra-day and inter-day repeatability were found to be 3.7 %–4.6 % and 4.5 %–6.2 %, respectively. The suggested PT-SPE method is simple, low cost, rapid, and efficient to extract SAs, and can be applied for the monitoring of SAs residues in the aquatic environment and in food.

Highly degradable bio-based plastic with water-assisted shaping process and exceptional mechanical properties

The fabrication of biodegradable and recyclable bio-based plastic by complexing carboxymethyl cellulose (CMC) and cationic polymeric ionic liquid (PILCl) assisted with KNO3 is offered to utilize plastics sustainably and mitigate serious threats to the environment. The CMC/PIL plastic film, formed via electrostatic interactions, exhibits exceptional mechanical properties that surpass those of most conventional plastics. It demonstrates a tensile strength of approximately 200 MPa and a Young's modulus of around 5.5GPa. Even after recycling and regeneration, they essentially retain the original mechanical characteristics with a tensile strength of about 190 MPa. These CMC/PIL plastic films can be processed into three-dimensional (3D) shapes assisted with water and their fundamental qualities maintain after numerous shaping. Besides, they possess excellent biodegradability and can finish biodegrading in a few hours with cellulase and within a few days when exposed to soil. This innovation provides a fresh and practical way to produce degradable plastics.

Polymer Gels from Physical Entanglements of Ultrahigh–Molecular Weight Polymers in Ionic Liquids

Polymer Gels from Physical Entanglements of Ultrahigh–Molecular Weight Polymers in Ionic Liquids

Ruthenium nanoparticle immobilised on ionic liquid polymer as efficient catalyst for the hydrolysis of NaBH4

Development of heterogeneous catalyst is significant key for achieving high performance of NaBH4 hydrolysis to produce hydrogen. The stability of sodium borohydride in the presence of suitable catalyst is the efficient method to generate hydrogen. In this work, styrene-imid PIILP, polymer 1 decorated styrene, imidazolium ionic liquid, and cross-coupling is successfully synthesised by AIBN initiated radical polymerisation, then precipitation with 3,3′,3″phosphinetriyltribenzene sulfonate with ratio (1:0.3) to isolate the first styrene-imid- sulphonated PIILP, polymer 2. RuNP@styrene-imid-sulphonated PIILP, RuNPs catalyst 3 was synthesised by impregnation with RuCl3, then reduction by NaBH4. Moreover, several analytical techniques such as, 31P, 1H, 13C solid-state NMR, CHN, IR, XPS, TEM, TGA-DTA, and SEM were examined to explore the obtained catalyst 3. The hydrogen generation from NaBH4 utilizing catalyst 3 was exhibited the catalytic behaviour studying several parameters such as, temperature, catalytic loading, and NaBH4 concentrations this work was deducted the activation energy (30.32 kJmol-1), and the turnover frequency (TOF) reached up 134.9, 112.77, and 98.38 moleH2.molcat−1.min−1 at 40, 35 and 30 °C. The effectiveness of Ruthenium nanoparticle catalyst 3 for the hydrolysis reaction of NaBH4 was examined in H2O and D2O resulting kinetic isotope effect (KIE) kH/kD = 3. In addition, RuNPs demonstrated a promising efficient for reuse catalyst 3 after five cycles for the catalytic hydrolysis.

Investigation of PVDF‐co‐HPF based ultrafiltration polymer inclusion membrane for the extraction of cadmium ions

AbstractUltrafiltration polymer inclusion membranes (UPIMs) have become increasingly significant for the separation and purification of heavy metals from industrial wastes and wastewater due to their convenience compared to other liquid membranes. A novel process for cadmium separation and recovery has been developed using biodegradable ion carriers, specifically room temperature ionic liquids with various molecular structures. This innovation has greatly enhanced the efficiency and application of UPIMs for cadmium separation, while also providing the membranes with unique functional properties. In this study, various UPIMs were produced using polyvinyl fluoride hexafluoropropylene (PVDF‐co‐HPF) as the base polymer, different plasticizers, and symmetric room temperature ionic liquids as ion carriers. The ability of these membranes to extract cadmium ions was evaluated, demonstrating a removal rate of 9.70 μmol s−1 from a 25 ppm Cd(II) solution under optimum conditions. The selectivity and stability of the optimized UPIM were examined under different conditions to obtain a deeper insight into of its performance. The morphological characteristics of the optimized UPIM were examined using scanning electron microscopy and atomic force microscopy techniques.

Poly(ionic liquids-acrylic acid)-modified MIL-101(Cr) metal−organic frameworks: Preparation and efficient adsorption of europium☆

A novel composite material, Poly(IL-AA)@MIL-101(Cr), combining metal-organic framework, polymeric ionic liquid and acrylic acid, was synthesized for the selective and efficient adsorption of rare earths europium(III) (Eu3+). Characterization of the materials was carried out using techniques such as X-ray diffraction (XRD), Fourier transform infrared (FTIR), scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS), thermogravimetric analysis (TGA) and Brunauer-Emmett-Teller (BET). The results demonstrate successful incorporation of the polymeric ionic liquid onto the material surface while preserving the crystal structure and morphology of MIL-101(Cr). Adsorption experiments were conducted to explore parameters including solution pH, initial Eu3+ concentration, and duration, with comprehensive analyses of adsorption kinetics, isotherms, and mechanisms. Findings reveal that Poly(IL1-AA)@MIL-101(Cr), Poly(IL3-AA)@MIL-101(Cr), and Poly(IL5-AA)@MIL-101(Cr) achieve adsorption equilibrium for Eu3+ at approximately 9 h with an equilibrium pH of 6.2. The adsorption of Eu3+ predominantly follows a pseudo-second-order kinetic model and Langmuir isotherm adsorption model. Moreover, the prepared composite material exhibits superior adsorption selectivity for Eu3+ over other metal ions in the mixture (K+, Mg2+, Ni2+, Co2+, Zn2+, La3+, and Nd3+). Even after five adsorption-desorption cycles, the composite material maintains satisfactory adsorption performance.

Scaling Relation and Rheological Behaviors of Polymerized Ionic Liquids in Ionic Liquid/Dimethylformamide Solutions

Scaling Relation and Rheological Behaviors of Polymerized Ionic Liquids in Ionic Liquid/Dimethylformamide Solutions

Polymeric ionic liquids containing copper(I) and copper(II) ions as gas chromatographic stationary phases for olefin separations

Copper(I) ions (Cu+) are used in olefin separations due to their olefin complexing ability and low cost, but their instability in the presence of water and gases limits their widespread use. Ionic liquids (ILs) have emerged as stabilizers of Cu+ ions and prevent their degradation, providing high olefin separation efficiency. There is limited understanding into the role that polymeric ionic liquids (PILs), which possess similar structural characteristics to ILs, have on Cu+ ion-olefin interactions. Moreover, copper ions with diverse oxidation states, including Cu+ and Cu2+ ions, have been rarely employed for olefin separations. In this study, gas chromatography (GC) is used to investigate the interaction strength of olefins to stationary phases composed of the 1-hexyl-3-methylimidazolium bis[(trifluoromethyl)sulfonyl]imide ([C6MIM+][NTf2−]) IL and the poly(1-hexyl-3-vinylimidazolium [NTf2−]) (poly([C6VIM+][NTf2−])) PIL containing monovalent and divalent copper salts (i.e., [Cu+][NTf2−] and [Cu2+]2[NTf2−]). The chromatographic retention of alkenes, alkynes, dienes, and aromatic compounds was examined. Incorporation of the [Cu2+]2[NTf2−] salt into a stationary phase comprised of poly(dimethylsiloxane) resulted in strong retention of olefins, while its addition to the [C6MIM+][NTf2−] IL and poly([C6VIM+][NTf2−]) PIL allowed for the interaction strength to be modulated. Olefins exhibited greater affinities toward IL and PIL stationary phases containing the [Cu2+]2[NTf2−] salt compared to those with the [Cu+][NTf2−] salt. Elimination of water from both copper salts was observed to be an important factor in promoting olefin interactions, as evidenced by increased olefin retention upon exposure of the stationary phases to high temperatures. To evaluate the long-term thermal stability of the stationary phase, chromatographic retention of probes was measured on the [Cu2+]2[NTf2−]/[C6MIM+][NTf2−] IL stationary phase after its exposure to helium at a temperature of 110 °C.

Retraction Note: Comparing ion transport in ionic liquids and polymerized ionic liquids

Retraction Note: Comparing ion transport in ionic liquids and polymerized ionic liquids

Liquid state theory of the structure of model polymerized ionic liquids.

We employ polymer integral equation theory to study a simplified model of semiflexible polymerized ionic liquids (PolyILs) that interact via hard core repulsions and short range screened Coulomb interactions. The multi-scale structure in real and Fourier space of PolyILs (ions chosen to mimic Li, Na, K, Br, PF6, and TFSI) are determined as a function of melt density, Coulomb interaction strength, and ion size. Comparisons with a homopolymer melt, a neutral polymer-solvent-like athermal mixture, and an atomic ionic liquid are carried out to elucidate the distinct manner that ions mediate changes of polymer packing, the role of excluded volume effects, and the influence of chain connectivity, respectively. The effect of Coulomb strength depends in a rich manner on ion size and density, reflecting the interplay of steric packing, ion adsorption, and charge layering. Ion-mediated bridging of monomers is found, which intensifies for larger ions. Intermediate range charge layering correlations are characterized by a many-body screening length that grows with PolyIL density, cooling, and Coulomb strength, in disagreement with Debye-Hückel theory, but in accord with experiments. Qualitative differences in the collective structure, including an ion-size-dependent bifurcation of the polymer structure factor peak and pair correlation function, are predicted. The monomer cage order parameter increases significantly, but its collective ion counterpart decreases, as ions become smaller. Such behaviors allow one to categorize PolyILs into two broad classes of small and large ions. Dynamical implications of the predicted structural results are qualitatively discussed.

PROTIC POLYMERIC IONIC LIQUID OF A BLOCK OLIGOMERIC STRUCTURE WITH IONIC BONDS IN THE MAIN CHAIN

A method for the synthesis of protic polymeric ionic liquid (PIL) of a block oligomeric structure with ionic bonds in the main chain, which turns into a liquid state at temperatures below 50 °C, was developed. Ionic bonding was used to form a polymer chain. It was formed as a result of neutralization reaction between oligomers of telechelic structure with terminal acidic and basic groups. A new linear oligomer containing basic tertiary nitrogen atoms at the ends of the oligoether chain (PEO-2NEt2) was obtained by reaction of α,ω-diglycidyl ether of polyethylene glycol MW 1000 with N,N-diethylamine. A linear oligomer with terminal sulfonic acid groups (PEO-2SO3H), which is a product of the interaction of polyethylene glycol (MW 1000) with the cyclic anhydride of 2-sulfobenzoic acid, was used as an acidic linear oligomer. The synthesis of PIL [PEO-2H-2NEt2]2+ [PEO-2SO3]2- was carried out by neutralization of basic oligomer PEO-2NEt2 with the acidic oligomer PEO-2SO3H in their molar ratio of 1:1. The structure of the obtained compound was characterized by the methods of FTIR and 1H NMR spectroscopy. According to the DSC data, the synthesized PIL contains an amorphous phase with a glass transition temperature of -49.7 °С and a crystalline phase with a melting temperature of 34.5 °С. The decomposition onset temperature corresponding to 5% weight loss is 271 °C according to the TGA. The ionic conductivity of PIL studied by dielectric relaxation spectroscopy under anhydrous conditions in the range from 40 °C to 100 °C increases with increase in temperature and reaches 2.7·10-4 S/cm. The resulting compound is promising as a proton-conducting medium for various electrochemical devices.

Core/shell Ni@C particle-supported N-doped carbon with hollow capsules for efficient electrocatalytic reduction of oxygen

To replace the noble metal catalysts for oxygen reduction reaction (ORR), a Ni@C-supported N-doped carbon material (Ni@C/NC) is in-situ prepared via one-step pyrolyzing the polymerizable ionic liquid of vinyl imidazole combined with Ni(NO3)2. Systemic investigations demonstrate that these nanosized Ni particles are tightly wrapped with a thin carbon layer to form the core/shell structure, meanwhile carbon capsules are synchronously yielded on the carbon matrix. As a result, both the carbon shell and the carbon capsule jointly increase the active sites of the Ni@C/NC, while the carbon shell also contributes the fast electron-transfer from Ni particle. Compared with the normal Ni-supported carbon catalyst, the Ni@C/NC shows the respectable ORR performance with the onset and half-wave potentials of 0.96 and 0.84 VRHE. After the long-term electrocatalysis (10 h), the Ni@C/NC is found to possess the great structural and electrocatalytic stabilities, which maintains 93 % of the initial current density and the well-dispersed and uniform Ni@C particles. Subsequently, a Zn-Air battery with the Ni@C/NC cathode is assembled and exhibits a peak power density of 200 mW cm−2. Therefore, the as-obtained Ni@C/NC with the high electroactivity and stability can be expected as an ideal candidate to apply in the metal-air batteries and fuel cells in the future.

Development of an asymmetric cellulose acetate-ionic liquid P6,6,6,14[PHOS] gel membrane for the perstraction of succinic acid from a model fermentation solution of yarrovia lipolytica

This study introduces a novel approach to separate succinic acid (SA) from fermentation mixtures using an asymmetric membrane based on the gelation of the ionic liquid [P6,6,6,14][PHOS] coated with two layers of cellulose acetate. The membrane was designed to explore the synergistic effect of polymer-ionic liquid interfaces according to the solution-diffusion theory. The gelation of the ionic liquid was achieved using 12-hydroxystearic acid at a concentration of 1.5%, allowing the use of ionic liquid gels as new materials for the generation of membranes. The perstraction performance of the membrane was evaluated over 5 h at two different temperatures (25°C and 37°C), with an initial feed solution concentration of 50 kg m−3 for SA and glycerol and pure water as a receiving phase., Several flow rates and phase-volume ratios were studied anda mass transfer model based on the resistance-in-series theory was assessed to understand the behavior of each mass transfer stage considering the distribution in each interphase. Interestingly, optimal perstraction results were obtained at 37°C, with an average transmembrane flux of 0.22 kg m-2h−1 for SA, an extraction percentage of 43.1% for SA and 0.7% for glycerol, and a SA/glycerol selectivity of 54.98. Besides presenting a novel composite membrane, this study reports pioneering perstraction outcomes, highlighting its potential as an innovative SA separation strategy and structured new materials for selective extractions.

Highly acid-stable high-temperature proton exchange membrane: Azide-based polymeric ionic liquids for the enhancement of amino-polybenzimidazole

Polybenzimidazole (PBI) is commonly used for high-temperature proton exchange membranes. However, it is undeniably challenging for phosphoric acid (PA)-doped PBI membranes to have both high proton conductivity and excellent long-term stability. In this study, a series of polymer ionic liquid composite PBI membranes were fabricated. These membranes are made using two azide-functional ionic liquids and amino-polybenzimidazole, adjusting the amount of the two ionic liquids. The ionic pairs offered by the ionic liquids positively impact the transportation of protons and the stability of PA through the replacement of anions. It is noteworthy that crosslinked amino-polybenzimidazole membranes containing functional polymeric ionic liquids have proton conductivity of up to 131.7 mS cm−1 at 180 °C, and the PA retention after 240 h at 160 °C under humidity-free conditions is 86.5 %. In addition, the membrane is used in membrane electrodes with hydrogen and oxygen at the anode and cathode, respectively, exhibiting a peak power density of 694.6 mW cm−2 at 160 °C. And the voltage decay rate is 0.28 mV h−1 after long-term test. The findings indicate that membranes made of functional polymeric ionic liquids crosslinked with amino-polybenzimidazoleprovide a new strategy to enhance fuel cell durability.

From Synthesis to Functionality: Tailored Ionic Liquid-Based Electrospun Fibers with Superior Antimicrobial Properties.

Herein, we report an efficient and facile strategy for the preparation of imidazolium-based ionic liquid (IL) monomers ([CnVIm][Br], n = 2, 4, 6, 8, 10, and 12) and their corresponding polymeric ionic liquids (PILs) with potent antimicrobial activities against Gram-negative and Gram-positive bacteria and fungi. The electrospinning technique was utilized to tailor the polymers with the highest antimicrobial potency into porous membranes that can be easily implemented into diverse systems and extend their practical bactericidal application. The antimicrobial mechanism of obtained ILs, polymers, and nanomaterials is considered concerning the bearing chain length, polymerization process, and applied processing technique that provides a unique fibrous structure. The structure composition was selected due to the well-established inherent amphiphilicity that 1-alkylimidazolium ILs possess, coupled with proven antimicrobial, antiseptic, and antifungal behavior. The customizable nature of ILs and PILs complemented with electrospinning is exploited for the development of innovative antimicrobial performances born from the intrinsic polymer itself, offering solutions to the increasing challenge of bacterial resistance. This study opens up new prospects toward designer membranes providing a complete route in their designing and revolutionizing the approach of fabricating multi-functional systems with tunable physicochemical, surface properties, and interesting morphology.

Ionic liquid-reinforced transparent, stretchable, conductive organic ionic gel with ultra-high sensory capability and ultra-robust impact-resistance

Traditional conductive hydrogels face challenges in environmental stability and mechanical limitations, constraining their applications in wearable devices. Here, we present a novel organic ionic gel by the construction of PVA/EG double polymer network and ionic liquid, named POIG. It showcases outstanding tensile strength (3.01 MPa) and extensibility (820 %). POIG excels in both low and high-speed impacts, dissipating over 90 % of energy in low-speed impacts and outperforming commercial foam five times in high-speed impacts (1.4 kJ/m). The addition of an ionic liquid in POIG creates a stable, uniform, and highly ordered internal conductive structure, leading to ultra-low strain responsiveness (0.2 %), ultra-fast response times (≈10 ms), high linearity (R2 = 0.999), and excellent sensing performance. High stability is also confirmed through 4000 cycles of both tensile and compression testing. Additionally, we developed a real-time sign language recognition system using deep learning, accurately identifying ten gestures with 98.5 % accuracy. This research offers a durable and innovative organic material for future wearable technology and smart devices.