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A protic ionic liquid (PIL) composed of 1,8-diazabicyclo[5.4.0]-undec-7-ene (DBU) and acetic acid can dissolve cellulose under mild conditions and catalyse its transesterification. To investigate the relationship between physicochemical properties and chemical structures, PILs composed of DBU and carboxylic acids with varying alkyl chain lengths were prepared as cellulose-dissolving solvents. The thermal behaviours of the PILs were analysed by thermogravimetry and differential scanning calorimetry, and their viscosities, ionic conductivities, and cellulose-dissolution abilities were determined. The effect of the alkyl chain length in the carboxylate ion on the physicochemical properties of the PILs was investigated. With increasing chain length, the thermal stability and ionic conductivity increased, whereas the melting point (T m), glass-transition temperature (T g), cellulose solubility, and viscosity decreased. The cellulose solubility increased as the difference between the p K a values of the DBU and carboxylic acid (Δp K a) increased. In addition, the cellulose solubility increased with the increasing density of the PIL. It was revealed that PILs with a high Δp K a value and a carboxylate ion with a short alkyl chain are suitable for cellulose dissolution. A protic ionic liquid (PIL) composed of 1,8-diazabicyclo[5.4.0]-undec-7-ene (DBU) and acetic acid can dissolve cellulose under mild conditions and catalyse its transesterification. In this study, PILs composed of DBU and carboxylic acids with varying alkyl chain lengths were prepared, and the relationship between physicochemical properties and chemical structures was investigated. [ABSTRACT FROM AUTHOR]

Regioregularpolythiophenes containing an optically active substituentin the third position of the thiophene ring, head-to-tailpoly(3-[2-((S)-1-methyloctyloxy)ethyl]thiophene)s(HT-P(S)MOETs), were synthesizedusing highly reactive zinc. For comparison, HT-P(R)MOET and achiral HT-P(±)MOET alsowere synthesized from R-type monomers and racemicmonomers, respectively. The HT-PMOET possessed greaterthan 95% head-to-tailcoupling with a weight-averagemolecular weight (Mw)between 1.96 × 104and 2.94 × 104.The polymers were characterized using 1H and 13C NMR, optical rotatory power measurements, circular dichroism (CD),and UV–vis spectroscopy. X-ray diffraction patterns of thecast films demonstrated that regioregular HT-PMOETpossessed a strong tendency to self-assemble into highly ordered,crystalline structures. The HT-P(S)MOET and HT-P(R)MOET showed strongCotton effects, while HT-P(±)MOET showed veryweak Cotton effects. The presence of a circular dichroism effect indicatedthat the side chain chirality induced optical activity in poly(thiophene)main chains. The monolayer formation of HT-PMOETspread on the water surface was characterized using a pressure–area(π–A) isotherm. The molecular areasof HT-P(S)MOET and HT-P(R)MOET molecules on the water surface were 33.5and 32.9 Å2, respectively, at 10 °C, which werelarger than that of HT-P(±)MOET (27.9 Å2), suggesting that optically active HT-PMOETexpanded because of the chiral repulsion between side chains. Multilayerfilms of HT-PMOET were prepared by repeating horizontaldeposition of the monolayer on the water surface. The multilayer filmsof optically active HT-PMOET obtained showed strongerCotton effects than did the cast films. In addition, electrical conductivitiesof HT-PMOET multilayer films were superior to thoseof spin-coated films. Head-to-tailpoly(3-[2-((S)-1-methylpropyloxy)ethyl]thiophene) (HT-P(S)MPET), which contained shorter side chain lengthscompared to HT-P(S)MOET, also wassynthesized. The CD intensities of HT-P(S)MPET multilayer films were smaller than those of HT-P(S)MOET multilayer films, suggesting that theoptically active side-chain length is critically important to theoptically active self-assembly. [ABSTRACT FROM AUTHOR]

Abstract: A regioregular polythiophene bearing an optically active substituent at the 3-position of thiophene ring, Head-to-Tail poly(3-[2-((S)-1-methyloctyloxy)ethyl]thiophene) (HT-P(S)MOET), was synthesized using highly reactive zinc. HT-P(S)MOET had more than 95% Head-to-Tail coupling with a Mw of 3.72×104 (Mw/Mn=1.20) as estimated by 1H-NMR spectroscopy and gel permeation chromatography. HT-P(S)MOET had strong negative Cotton effect at about 560 and 610nm and positive Cotton effect at about 490nm. The presence of circular dichroism effect shows that the chirality of side chains induces the optical activity in poly(thiophene) main chains. The Langmuir-Blodgett films of HT-P(S)MOET exhibited well-defined layer structure and unique optical properties. [Copyright &y& Elsevier]

Organic-inorganic semiconductor heterostructures have been successfully fabricated by incorporating a polydiacetylene backbone into layered perovskite compounds by photopolymerization. The γ-ray irradiation caused polymerization of aminodiacetylene cations, RNH 3 + , where R=CH 3 (CH 2 ) 13 C≡C-C≡CCH 2 , in the solid salts of (RNH 3 ) 2 PbBr 4 . Layered Perovskite Photopolymerization Quantum-well [ABSTRACT FROM AUTHOR]

Abstract: Novel organic–inorganic hybrid compounds, C16H44N4Pb3I10 and C14H34N2Pb2I6, were synthesized by solvent diffusion recrystallization from the dimethylsulfoxide solution containing PbI2 and gemini ammonium surfactants with different head groups. The results of single crystal X-ray structural analysis showed that the inorganic region of C16H44N4Pb3I10 has quasi one-dimensional chains of [Pb3I10]4− units, whereas that of C12H30N2Pb2I6 has one-dimensional chains of face-sharing PbI6 octahedra. The absorption and fluorescence spectra of these compounds also indicate the formation of one-dimensional inorganic chains and quantum-confined structures. [Copyright &y& Elsevier]

A 2D perovskite incorporating an amine moiety with a carboxy group exhibited orientation changes as the amount of DMSO additive varied. The degree of perpendicular orientation was increased by optimizing the amount of DMSO additive, while using the bar-coating method. Moreover, film thickness and the ratio of perpendicular orientation exhibited a positive correlation. [ABSTRACT FROM AUTHOR]

Acetone, regarded as a poor solvent for perovskite materials, was found to be suitable for synthesis of the perfluoroalkyl-based two-dimensional (2D) perovskite (C3F7CH2NH3)2PbBr4. One-step synthesis gave this material as a pure phase exhibiting quantum- and dielectric-confinement effects. However, N,N-dimethylformamide (DMF), a traditional perovskite solvent, did not produce these properties. [ABSTRACT FROM AUTHOR]

Abstract Organic ionic plastic crystals (OIPCs) have been studied as solid-state electrolytes because of their desirable properties such as non-flammability, plasticity, and ionic conductivity. However, the temperature range of their conductive plastic crystal phase is narrow. We previously reported that N -ethyl- N -methylpyrrolidinium bis(fluorosulfonyl)amide ([C 2 mpyr][FSA]) exhibited a wide temperature range of plastic crystal behavior and high ionic conductivity at room temperature. In this study, the relationship between the side chain structure of pyrrolidinium and the physicochemical properties of their compounds with FSA was investigated. With two introduced ethyl groups, N , N -diethylpyrrolidinium bis(fluorosulfonyl)amide ([C 2 epyr][FSA]) showed higher ionic conductivity than [C 2 mpyr][FSA], while maintaining a sufficient temperature range of plastic crystal phase. The ionic conductivity of [C 2 epyr][FSA] was further improved by the addition of 5 mol% LiFSA. For the [C 2 epyr][FSA] composited with 5 mol% LiFSA, the lithium transference number was determined to be 0.27 at 60 °C. Reversible lithium plating/stripping reaction was observed on a Ni electrode in the CV measurement. Symmetric pyrrolidinium cation with a longer alkyl chain (up to two carbons) showed conductive plastic solid phase in a wide temperature range and a higher lithium transference number. Graphical abstract Image 1 Highlights • Plastic crystals synthesized with different pyrrolidinium cations and FSA anion. • Ionic conductivity increased with increasing alkyl chain length on the cation. • Li transference number of LiFSA-doped pyrrolidinium salts was 0.27 at 60 °C. [ABSTRACT FROM AUTHOR]

In this work, pyrrolidinium-based OIPCs were synthesised together with various anionic species to investigate the effect of the anion structure on the OIPC properties. In particular, the relationship between the ionic conductivity and ionic radius ratio (ρ) of the anion and cation was investigated. The results suggested that OIPCs with a smaller ρ value were found to exhibit a higher ionic conductivity. [ABSTRACT FROM AUTHOR]

Abstract: This study demonstrates the supramolecular chirality control of a conjugated polymer via solvent polarity. We designed and synthesized a chiral polyfluorene‐thiophene copolymer having two different chiral side chains at the 9‐position of the fluorene unit. Chiral cyclic and alkyl ethers with different polarities were selected as the chiral side chains. The sign of the circular dichroism spectra in the visible wavelength region was affected by the solvent system, resulting from the change of supramolecular structure. The estimation of the solubility parameter revealed that the solubility difference of the side chains contributed to the change of the circular dichroism sign, which was also observed in spin‐coated films prepared from good solvents having different polarities. [ABSTRACT FROM AUTHOR]

Ionic liquids (ILs) containing zwitterions have been studied as electrolytes for lithium-ion batteries (LIBs). The effects of addition of a pyrrolidinium zwitterion in an IL electrolyte on the thermal and electrochemical stability and charge/discharge properties of Li/LiCoO 2 and graphite/Li cells were investigated. The thermal decomposition temperature of the IL electrolyte composed of N -methyl- N -propylpyrrolidinium bis(fluorosulfonyl)amide ([P13][FSA])/lithium bis(trifluoromethylsulfonyl)amide (LiTFSA) with 3-(1-butylpyrrolidinium)propane-1-sulfonate (Bpyps) as the zwitterionic additive, the thermal decomposition temperature was about 300 °C. The electrochemical window of [P13][FSA]/LiTFSA/Bpyps was 0–+5.4 V vs. Li/Li + , which was almost identical to that of [P13][FSA]/LiTFSA. Li|electrolyte|LiCoO 2 cells containing the IL/Bpyps electrolyte system exhibited high capacities in the cut-off voltage range of 3.0–4.6 V, even after 50 cycles. The increase in the interfacial resistance between the electrolyte and cathode with cycling was suppressed. In the cyclic voltammograms of cells employing a graphite electrode, the intercalation/deintercalation of lithium ions were observed in the range of 0 and + 0.4 V vs. Li/Li + . Further, graphite|electrolyte|Li cells containing [P13][FSA]/LiTFSA/Bpyps exhibited stable charge/discharge cycle behaviour over 50 cycles. [ABSTRACT FROM AUTHOR]

The ionic liquid (IL) N -Methyl- N -methoxymethylpyrrolidinium bis(fluorosulfonyl)amide ([Pyr 1,1O1 ][FSA]) was synthesized, and its physicochemical and electrochemical properties were investigated with respect to its application as an electrolyte in lithium-ion secondary batteries operating over a wide temperature range. [Pyr 1,1O1 ][FSA]/Li salt (0.34 mol kg −1 ) composites were prepared by adding lithium bis(trifluoromethylsulfonyl)amide (LiTFSA) into the IL. [Pyr 1,1O1 ][FSA] and [Pyr 1,1O1 ][FSA]/LiTFSA exhibited melting temperatures ( T m ) below −30 °C. [Pyr 1,1O1 ][FSA] exhibited a higher ionic conductivity value as compared with that of the corresponding IL with only alkyl substituents. The electrochemical window for both [Pyr 1,1O1 ][FSA] and [Pyr 1,1O1 ][FSA]/LiTFSA was 5.1 V. Stable lithium deposition and dissolution occurred on a Ni electrode at 25 °C. [ABSTRACT FROM AUTHOR]

Rechargeable magnesium (Mg) batteries are envisioned as next generation batteries. The development of solid polymer electrolytes with high ionic conductivity will contribute to realize not only high performance Mg batteries but also reliable and safe devices. In this study, diblock copolymers (PPEGMAm‐b‐SPBn) with oligoether (PEGMA) and zwitterionic (SPB) side‐chains are synthesized in order to develop novel Mg‐ion electrolytes. PPEGMAm‐b‐SPBn copolymers with various unit ratios are synthesized by reversible addition‐fragmentation chain transfer (RAFT) polymerization. PPEGMAm‐b‐SPBn exhibited two distinct glass transition temperatures. Phase‐separated structures are observed by atomic force microscope (AFM) measurements. PPEGMAm‐b‐SPBn/Mg‐salt composites exhibited a glass transition temperature due to the mixture formation of PEGMA and SPB blocks. When the unit numbers of m and n are 44 and 75, respectively, PPEGMAm‐b‐SPBn/Mg‐salt ([EO]: [Mg] = 6: 1) exhibits the highest ionic conductivity of over 10−4 S cm−1 at 60 °C among 11 composites prepared in this study. [ABSTRACT FROM AUTHOR]

Abstract: Multilayer-type polymer electrolyte membranes composed of a sulfonated poly(4-phenoxybenzoyl-1,4-phenylene) (S-PPBP) layer and a mono[poly(propylene oxide)methacrylate]phosphate ester (PPHP) layer were fabricated by solution-casting procedure (Method 1) and hot-pressing procedure (Method 2) in order to suppress methanol permeability of electrolyte membranes. No delamination was observed by SEM measurements of S-PPBP/PPHP interfaces, indicating that PPHP had good adhesive properties to S-PPBP surfaces. The methanol permeability of S-PPBP/PPHP membranes was lower than that of S-PPBP membranes and decreased with increasing the thickness of PPHP layers. The bilayer membrane with 12μm PPHP and 40μm S-PPBP layers showed a methanol permeability of 2.97×10−7 cm2 s−1 in 1moldm−3 methanol aqueous solution at 25°C, which was 13% less than that of the S-PPBP membranes. The conductivity of this membrane reached its optimum with values as high as 1.57×10−1 Scm−1 at 80°C and 90%RH. [Copyright &y& Elsevier]

Poly (ethylene oxide) (PEO) has been investigated as an ion-conductive matrix for several decades due to its excellent properties. However, further improvements are needed to enable a PEO-based ion-conductive matrix for practical applications. In order to develop novel solid polymer electrolytes based on zwitterions, we synthesized diblock copolymers (PPEGMA-b-SPBs) with oligoether and zwitterionic side-chains and evaluated their physico-chemical properties. PPEGMA-b-SPBs with various unit ratios were synthesized by RAFT polymerization. PPEGMA-b-SPBs with/without LiTFSA exhibited two distinct glass transition temperatures regardless of the unit ratio of PEGMA and SPB. AFM observations clearly revealed phase-separated structures. The ionic conductivity of PPEGMA-b-SPBs increased even at a high salt concentrations such as [EO]:[Li] = 6:1 and was over 10−5 S cm−1 at 25 °C. This tendency is unusual in a PEO matrix. The oxidation stability of PPEGMA-b-SPBs was about 5.0 V vs. Li/Li+, which is a higher value than that of PEO. The improvement of the electrochemical properties is attributed to the introduction of the SPB block into the block copolymers. PPEGMA-b-SPBs were evaluated as cathode-coating materials for Li batteries. The discharge capacity and coulombic efficiency of the cells employing the cathode (LiNi1/3Mn1/3Co1/3O2 (NMC)) coated with the block copolymers were much higher than those of the cell employing the pristine cathode at the 50th cycle in the cut-off voltage range of 3.0–4.6 V. [ABSTRACT FROM AUTHOR]

An imidazolium-based zwitterion containing two oxyethylene units was obtained as a colorless liquid at room temperature. The equimolar mixture of the liquid zwitterion and lithium bis(trifluoromethylsulfonyl)amide showed an ionic conductivity of over 10−4S cm−1at 80 °C, which was higher than those of mixtures composed of analogous solid zwitterions. [ABSTRACT FROM AUTHOR]

Cellulose acetate (CA) is a resin derived from biomass. In addition to its various superior properties, CA is preferable to existing petroleum-derived resins from the viewpoint of green chemistry. Therefore, the acetylation of cellulose is one of the most important subjects in cellulose research. In this study, we found that the acetylation of cellulose could proceed in some protic ionic liquids (PILs) composed of amidine and acetic acid with ΔpKa = ca. 8.4–8.7 under mild conditions without any catalyst. The degree of substitution (DS) of the produced CA was above 1.84, and the maximum DS was 2.87 when the ΔpKa of the PIL was about 8.5. In propionate-based PILs, cellulose was not only acetylated but also propionated; however, the cellulose acetylation did not occur in formate-based PILs. It was revealed that the esterification of cellulose proceeded through the anion exchange between carboxylic anhydride and anion species of the PIL. [ABSTRACT FROM AUTHOR]

Ionic liquids (ILs) containing zwitterions were studied as electrolytes for lithium-ion batteries. The effect of a pyrrolidinium zwitterion with a long ether side chain on the thermal and electrochemical properties of an IL and the charge/discharge properties of Li/LiCoO 2 , Li/LiNi 1/3 Mn 1/3 Co 1/3 O 2 (NMC), and graphite/Li cells with IL/zwitterion electrolytes was investigated. The melting temperature of the IL-based electrolyte composed of N -methyl- N -methoxymethylpyrrolidinium bis(fluorosulfonyl)amide ([Pyr 1,1O1 ][FSA]) and lithium bis(fluorosulfonyl)amide (LiFSA) with 3-(1-(2-(2-methoxyethoxy)ethyl)pyrrolidin-1-ium-1-yl)propane-1-sulfonate (OE2pyps) as the zwitterionic additive was about −18 °C. The electrochemical window of [Pyr 1,1O1 ][FSA]/LiFSA/OE2pyps was over 5 V vs. Li/Li + . Li|electrolyte|LiCoO 2 cells containing the [Pyr 1,1O1 ][FSA]/LiFSA/OE2pyps electrolyte system exhibited high capacity values in the cut-off voltage range of 3.0–4.3 V, even after 50 cycles. Moreover, increases of interfacial resistance between the electrolyte and cathode during cycling were suppressed. Li|electrolyte|NMC cells containing this electrolyte system also exhibited high capacities in a wide cut-off voltage range of 3.0–4.6 V, even after 50 cycles. In the cyclic voltammograms of cells employing a graphite electrode, the intercalation/deintercalation of lithium ions was observed between 0 and + 0.4 V vs. Li/Li + . Further, graphite|electrolyte|Li cells containing [Pyr 1,1O1 ][FSA]/LiFSA/OE2pyps exhibited stable charge/discharge cycle behavior over 5 cycles. [ABSTRACT FROM AUTHOR]

We demonstrate efficiency enhancement in perovskite solar cells (PSCs) utilizing a free-dopant hole transporting material (HTM), non-peripherally substituted octapentyl phthalocyanine (C5PcH 2 ) with thermal annealing. Particularly, by using thermal annealing approach, the external quantum efficiency at around 480 nm increase from 78 to 84%. Hence, the fill factor and short-circuit current density are markedly improved from 0.35 ± 0.02 to 0.55 ± 0.05 and from 18 ± 1 to 18.8 ± 0.3 mA cm -2 , respectively. Finally, the best device is achieved with power conversion efficiencies of 12.2% by annealing at 130 °C for 10 min. The photoluminescence and photo-induced charge carrier extraction in linearly increasing voltages measurements indicate that the charge carrier mobility in C5PcH 2 increases, and thereby the hole extraction and transportation from the perovskite layer to the Au anode as well the photovoltaic performance of PCS is improved by using thermal annealing processing. [ABSTRACT FROM AUTHOR]

Zwitterions with a cyano group on the side chain (CZ) were synthesized. Although the addition of CZ caused a slightly negative effect on viscosity, ionic conductivity, limiting current density, and lithium transference number, the oxidation limit of PEGDME/lithium bis(trifluoromethylsulfonyl)amide (LiTFSA) composites was improved to over 5 V. For charge/discharge testing using Li|electrolyte|LiCoO 2 cells, the cycle stability of PEGDME/LiTFSA with CZ in the voltage range of 3.0–4.6 V was much higher than that of PEGDME/LiTFSA. Incorporating a small mole fraction of CZ into PEGDME-based electrolytes prevented an increase in the interface resistance between the electrolyte and cathode with increasing numbers of the cycle. [ABSTRACT FROM AUTHOR]

Solid polymer electrolytes show great potential in electrochemical devices. Poly(ethylene oxide) (PEO) has been studied as a matrix for solid polymer electrolytes because it has relatively high ionic conductivity. In order to investigate the effect of zwitterions on the electrochemical properties of poly(ethylene glycol) dimethyl ether (G5)/lithium bis(fluorosulfonyl) amide (LiFSA) electrolytes, a liquid zwitterion (ImZ2) was added to the G5-based electrolytes. In this study, G5, which is a small oligomer, was used as a model compound for PEO matrices. The thermal properties, ionic conductivity, and electrochemical stability of the electrolytes with ImZ2 were evaluated. The thermal stabilities of all the G5-based electrolytes with ImZ2 were above 150 °C, and the ionic conductivity values were in the range of 0.8–3.0 mS cm −1 at room temperature. When the electrolytes contained less than 5.5 wt% ImZ2, the ionic conductivity values were almost the same as that of the electrolyte without ImZ2. The electrochemical properties were improved with the incorporation of ImZ2. The anodic limit of the electrolyte with 5.5 wt% ImZ2 was 5.3 V vs. Li/Li + , which was over 1 V higher than that of G5/LiFSA. [ABSTRACT FROM AUTHOR]

Abstract: Ni(0)-catalyzed coupling polymerization of 2,5-dichloro-4′-phenoxybenzophenone was investigated by varying the ligand and coligand, temperature, reaction time, and solvent. The weight-average molecular weight (Mw ) of poly(4-phenoxybenzoyl-1,4-phenylene)s (PPBPs) could be controlled by the polymerization conditions and reached a maximum of 4.4×105 gmol−1. Sulfonated PPBPs (S-PPBPs) with various Mw s were prepared with sulfuric acid to study the effect of molecular weight on the chemical and electrical properties of PPBP-based electrolytes. The strong molecular interactions in S-PPBP provided an ion exchange capacity of 2.9meqg−1 without loss of high mechanical properties. High molecular weight S-PPBPs had more desirable properties for fuel cell applications. While the swelling ratios and hydration numbers of S-PPBPs decreased with increasing molecular weight, the mechanical strength, proton conductivity, and fuel cell performance increased. S-PPBP also showed anisotropic behavior in the swelling and proton conductivity; such behavior is caused by the rigid-rod nature and the liquid-crystal structure. [Copyright &y& Elsevier]

Abstract: The relationships between morphology and proton conduction for Nafion membranes and hydrocarbon-type proton exchange membranes, namely, sulfonated poly(arylene ether ether ketone) (S-PEEK) and sulfonated poly(arylene ether sulfone) (S-PES), were investigated by small-angle X-ray scattering (SAXS) and atomic force microscopy (AFM). The direct simultaneous observation of surface morphology and active regions of proton conduction on membranes by combined high-resolution AFM phase imaging and an electrochemical technique at controlled humidity provided significant morphological information, particularly for the hydrocarbon-type membranes that exhibit few or no features on SAXS profiles. For the Nafion membranes, the active proton paths became denser and congregated with each other at over 60% RH, resulting in the formation of well-connected networks. For the hydrocarbon-type membranes, however, only the relatively small and dispersed proton paths were observed, which showed no significant change even as water content increased. We have demonstrated that the differences in microscopic morphology between the Nafion and hydrocarbon-type membranes are associated with the differences between their macroscopic proton conductivities. [Copyright &y& Elsevier]

Abstract: New proton-conducting polymer electrolyte membranes having phosphoric acid groups have been systematically synthesized. These homopolymers and copolymers were prepared by a conventional radical polymerization and a copolymerization with acrylonitrile or styrene or similar materials. The phosphoric acid groups can be cross-linked by heat treatments at 100°C, and hence their membranes showed excellent mechanical properties and chemical stability. Measurements of the water absorption and differential scanning calorimetry revealed that the copolymer membranes absorbed smaller amounts of water, which is freezing water under 90% RH, compared with the sulfonated polyelectrolyte membranes. The proton conductivity of the P-PHM membranes hydrated was measured to be 5.0×10-3Scm-1 at 100°C. This value was usually maintained up to 160°C. Dried homopolymer membranes and copolymer membranes were also examined for the water absorption and proton conductivity. It was found that the copolymerization with acrylonitrile provided good film-forming properties, thermal stability, and useful control of the physical and electrochemical properties. [Copyright &y& Elsevier]

A few kinds of thermoresponsive diblock copolymers have been synthesized and utilized for palladium-catalyzed coupling reactions in water. Poly(N-isopropylacrylamide) (PNIPAAm) and poly(N,N-diethylacrylamide) (PDEAAm) are employed for thermoresponsive segments and poly(sodium 4-styrenesulfonate) (PSSNa) and poly(sodium 2-acrylamido-methylpropanesulfonate) (PAMPSNa) are employed for hydrophilic segments. Palladium-catalyzed Mizoroki–Heck reactions are performed in water and the efficiency of the extraction process is studied. More efficient extraction was observed for the PDEAAm copolymers when compared with the PNIPAAm copolymers and conventional surfactants. In the study of the Sonogashira coupling reactions in water, aggregative precipitation of the products was observed. Washing the precipitate with water gave the product with satisfactory purity with a good yield. [ABSTRACT FROM AUTHOR]

Cellulose is the main component of biomass and is the most abundant biopolymer on earth; it is a non-toxic, low-cost material that is biocompatible and biodegradable. Cellulose gels are receiving increasing attention as medical products, e.g., as wound dressings. However, the preparation of cellulose hydrogels employing unmodified cellulose is scarcely reported because of the cumbersome dissolution of cellulose. In previous studies, we developed the new promising cellulose solvent N-butyl-N-methylpyrrolidinium hydroxide in an aqueous solution, which can dissolve up to 20 wt% cellulose within a short time at room temperature. In this study, we employed this solvent system and investigated the gelation behavior of cellulose after crosslinker addition. The swelling behavior in water (swelling ratio, water uptake), the mechanical properties under compression, and the antibacterial activity against Escherichia coli and Bacillus subtilis were investigated. We have developed a simple and fast one-pot method for the preparation of cellulose gels, in which aqueous pyrrolidinium hydroxide solution was acting as the solvent and as an antibacterial reagent. The pyrrolidinium hydroxide content of the gels was controlled by adjustment of the water volume employed for swelling. Simple recovery of the solvent system was also possible, which makes this preparation method environmentally benign. [ABSTRACT FROM AUTHOR]