Impact of ionic liquids on absorption behaviour of natural fibers/biopolyethylene biocomposites

AbstractFor many years, there has been a growing interest in technologies enabling the replacement of conventional polymer composites with new materials made from renewable raw materials. It is important to assess the behaviour of biocomposites in various environments, including humid conditions. Recently, ionic liquids have been studied as potential modificators of polymers properties, especially flame retardants. In previous study the impact of ionic liquids on thermal and mechanical properties of biocomposites was assessed. In this study the influence of ionic liquids on moisture absorption properties of biocomposites at different relative humidities (RH) was assessed. The biocomposites were built from polyethylene from renewable resources reinforced with flax or hemp fibers. The effect of the addition of 0.5, 1.0, 2.5 and 5 wt.% phosphonium ionic liquids on the moisture absorption properties of biopolyethylene biocomposite reinforced with natural fibers were tested. Mixtures of biopolyethylene, natural fibers and ionic liquid were calendered at 180 °C and then were compounded by injection moulding. The prepared samples were then characterized for their moisture uptake at 30%, 50% and 100% RH. Moisture absorption by biocomposites depended on the structure of the ionic liquid and the type of fiber. The saturation of moisture of about 0.054% was found for samples modified with tributylethylphosphonium diethyl phosphate and reinforced with flax and hemp fibers at RH 100%. The environmental resistance of the materials was found to be improved after the addition of trihexyltetradecylphosphonium bis (2,4,4-trimethylpentyl) phosphinate. Biocomposites with hemp fibers showed slightly less absorption than with flax fibers. It was also observed that ionic liquids: (bis (2,4,4-trimethylpentyl) phosphinate trihexyltetradecylphosphonate) and (bis (2-ethylhexyl) trihexyltetradecylphosphonium phosphate) protect PE biocomposites with plant fibers against mold in high humidity conditions (RH 100%).

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Controlled Nanostructuration of Cobalt Oxyhydroxide Electrode Material for Hybrid Supercapacitors

Materials ◽

10.3390/ma14092325 ◽

2021 ◽

Vol 14 (9) ◽

pp. 2325

Author(s):

Ronan Invernizzi ◽

Liliane Guerlou-Demourgues ◽

François Weill ◽

Alexia Lemoine ◽

Marie-Anne Dourges ◽

...

Keyword(s):

Ionic Liquid ◽

Ionic Liquids ◽

Energy Storage ◽

Specific Surface ◽

Electrode Materials ◽

Specific Capacity ◽

Hybrid Supercapacitors ◽

Cobalt Oxyhydroxide ◽

Precipitation Medium ◽

The Impact

Nanostructuration is one of the most promising strategies to develop performant electrode materials for energy storage devices, such as hybrid supercapacitors. In this work, we studied the influence of precipitation medium and the use of a series of 1-alkyl-3-methylimidazolium bromide ionic liquids for the nanostructuration of β(III) cobalt oxyhydroxides. Then, the effect of the nanostructuration and the impact of the different ionic liquids used during synthesis were investigated in terms of energy storage performances. First, we demonstrated that forward precipitation, in a cobalt-rich medium, leads to smaller particles with higher specific surface areas (SSA) and an enhanced mesoporosity. Introduction of ionic liquids (ILs) in the precipitation medium further strongly increased the specific surface area and the mesoporosity to achieve well-nanostructured materials with a very high SSA of 265 m2/g and porosity of 0.43 cm3/g. Additionally, we showed that ILs used as surfactant and template also functionalize the nanomaterial surface, leading to a beneficial synergy between the highly ionic conductive IL and the cobalt oxyhydroxide, which lowers the resistance charge transfer and improves the specific capacity. The nature of the ionic liquid had an important influence on the final electrochemical properties and the best performances were reached with the ionic liquid containing the longest alkyl chain.

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Amphiphilic ionic liquid induced fusion of phospholipid liposomes

Physical Chemistry Chemical Physics ◽

10.1039/d0cp04014b ◽

2020 ◽

Vol 22 (43) ◽

pp. 25255-25263

Author(s):

Sandeep Kumar ◽

Navleen Kaur ◽

Venus Singh Mithu

Keyword(s):

Ionic Liquid ◽

Ionic Liquids ◽

Structural Integrity ◽

Unilamellar Vesicles ◽

Phospholipid Liposomes ◽

Large Unilamellar Vesicles ◽

The Impact

The impact of increasing concentration of imidazolium-based ionic liquids ([CnMIM]+[Br]−) on the structural integrity of large unilamellar vesicles (LUVs) made of pure phosphatidylcholine (PC) and phosphatidylglycerol (PG) lipids.

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Synthesis and Characterization of Super-Molecular Ionic Liquids

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.197-198.906 ◽

2011 ◽

Vol 197-198 ◽

pp. 906-910

Author(s):

Hui Ru Liu ◽

Li Qiang Lv ◽

Xing Chen Zhang

Keyword(s):

Ionic Liquid ◽

Ionic Liquids ◽

Melting Point ◽

Quantum Chemical ◽

Organic Molecules ◽

Raw Materials ◽

Ammonium Thiocyanate ◽

Molar Ratio ◽

Molecular Ion

This study concerned a novel super-molecular ionic liquid synthesized by ammonium thiocyanate and caprolactam. The physical characters such as melting point and electric conductivity were investigated. Results showed that the melting point is -12.2°C at the molar ratio of 3:1 (caprolactam/ammonium thiocyanate), which is much lower than raw materials. The electric conductivities of synthesized ionic liquids were close to that of imidazole ILs. The structure of ionic liquid was characterized by IR,1HNMR and quantum chemical calculations. It was shown that the NH4+cation connected with caprolactam organic molecules by hydrogen bonds, leading to the forming of a super-molecular ion. The electrostatic attraction of super-molecular ion with anion was decreased because of the larger volume of super-molecular ion than original cation, thus the melting point decreased. The key properties that distinguish super-molecular ionic liquid from other ILs were the presence of supermolecular ion, which can be used to build up a hydrogen-bonded network. This type ion liquid was named as super-molecular ion liquid.

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The impact of ionic liquid fluorinated moieties on their thermophysical properties and aqueous phase behaviour

Physical Chemistry Chemical Physics ◽

10.1039/c4cp02008a ◽

2014 ◽

Vol 16 (39) ◽

pp. 21340-21348 ◽

Cited By ~ 24

Author(s):

Catarina M. S. S. Neves ◽

Kiki A. Kurnia ◽

Karina Shimizu ◽

Isabel M. Marrucho ◽

Luís Paulo N. Rebelo ◽

...

Keyword(s):

Ionic Liquid ◽

Ionic Liquids ◽

Aqueous Phase ◽

Thermophysical Properties ◽

Phase Behaviour ◽

Alkyl Chains ◽

The Impact

The presence of fluorinated alkyl chains in ionic liquids is quite relevant regarding their thermophysical properties and aqueous phase behaviour.

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Role of Cation in Enhancing the Conversion of the Alzheimer’s Peptide into Amyloid Fibrils Using Protic Ionic Liquids

Australian Journal of Chemistry ◽

10.1071/ch12316 ◽

2012 ◽

Vol 65 (11) ◽

pp. 1502 ◽

Cited By ~ 5

Author(s):

Natalie Debeljuh ◽

Swapna Varghese ◽

Colin J. Barrow ◽

Nolene Byrne

Keyword(s):

Ionic Liquid ◽

Ionic Liquids ◽

Primary Amine ◽

Amyloid Fibrils ◽

Tertiary Amines ◽

Protic Ionic Liquids ◽

Protic Ionic Liquid ◽

The Difference ◽

The Impact

We report on the impact of changes in the protic ionic liquid (pIL) cation on the fibrilisation kinetics and the conversion of the Aβ 16–22 from monomers to amyloid fibrils. When we compare the use of primary, secondary, and tertiary amines we find that the primary amine results in the greatest conversion into amyloid fibrils. We show that the pIL is directly interacting with the peptide and this likely drives the difference in conversion and kinetics observed.

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Dehydration of bioethanol with both pure ionic liquids and an ionic liquid anchored to mesoporous silica: A comparative study

CT&F - Ciencia Tecnología y Futuro ◽

10.29047/01225383.98 ◽

2018 ◽

Vol 8 (1) ◽

pp. 113-119 ◽

Cited By ~ 1

Author(s):

Luz A. Carreño-Díaz

Keyword(s):

Ionic Liquid ◽

Ionic Liquids ◽

Atmospheric Pressure ◽

Raw Materials ◽

Covalent Bond ◽

Mass Ratio ◽

Relative Volatility ◽

Imidazolium Chloride ◽

The Matrix ◽

Mesoporous Sio2

Bioethanol is produced by the fermentation of different raw materials; anhydrous ethanol is used as biofuel. This article reports the study of the dehydration of bioethanol by breaking the azeotrope, using ionic liquids as entrainers. Three ionic liquids (LIs) [EMIM][Cl], [EMIM][OAc], and [BMIM][Cl] were tested as entrainers; the behavior of ternary mixes of bioethanol-water-LI were evaluated through the activity coefficients and the relative volatility of bioethanol at 80°C and atmospheric pressure. In this first study it was concluded that the [EMIM][Cl] was the most effective IL for dehydration purposes: bioethanol (93.45 % v/v) after three cycles of extraction was (99.20 % v/v) when a mass ratio bioethanol-IL of 0.55 was used. Based on the first study, a composite was prepared by anchoring the LI 1-ethyl-(3-trimethoxysilil) propyl imidazolium chloride to mesoporous SiO2. The composite was characterized and it has been confirmed that there is a covalent bond between the IL and the matrix. The material was tested as dehydrating agent; results of these two studies were compared and showed that the pure ionic liquids could be used as entrainers in extractive distillations, breaking water-ethanol azeotrope, also showing the same ionic liquids able to be anchored to matrices as solid composites for dehydration, offering additional advantages such as selectivity, less time consuming, recyclability, and significantly diminishes (84%), the requirement for the amount of the IL.

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Ionic liquid pretreatment of stinging nettle stems and giant miscanthus for bioethanol production

Scientific Reports ◽

10.1038/s41598-021-97993-y ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Małgorzata Smuga-Kogut ◽

Daria Szymanowska-Powałowska ◽

Roksana Markiewicz ◽

Tomasz Piskier ◽

Tomasz Kogut

Keyword(s):

Ionic Liquid ◽

Ionic Liquids ◽

Enzymatic Hydrolysis ◽

Raw Materials ◽

Compositional Analysis ◽

Energy System ◽

Alcohol Concentration ◽

Bioethanol Production ◽

Stinging Nettle ◽

Giant Miscanthus

AbstractProduction of ethanol from lignocellulosic biomass is considered the most promising proposition for developing a sustainable and carbon–neutral energy system. The use of renewable raw materials and variability of lignocellulosic feedstock generating hexose and pentose sugars also brings advantages of the most abundant, sustainable and non-food competitive biomass. Great attention is now paid to agricultural wastes and overgrowing plants as an alternative to fast-growing energetic crops. The presented study explores the use of stinging nettle stems, which have not been treated as a source of bioethanol. Apart from being considered a weed, stinging nettle is used in pharmacy or cosmetics, yet its stems are always a non-edible waste. Therefore, the aim was to evaluate the effectiveness of pretreatment using imidazolium- and ammonium-based ionic liquids, enzymatic hydrolysis, fermentation of stinging nettle stems, and comparison of such a process with giant miscanthus. Raw and ionic liquid-pretreated feedstocks of stinging nettle and miscanthus were subjected to compositional analysis and scanning electron microscopy to determine the pretreatment effect. Next, the same conditions of enzymatic hydrolysis and fermentation were applied to both crops to explore the stinging nettle stems potential in the area of bioethanol production. The study showed that the pretreatment of both stinging nettle and miscanthus with imidazolium acetates allowed for increased availability of the critical lignocellulosic fraction. The use of 1-butyl-3-methylimidazolium acetate in the pretreatment of stinging nettle allowed to obtain very high ethanol concentrations of 7.3 g L−1, with 7.0 g L−1 achieved for miscanthus. Results similar for both plants were obtained for 1-ethyl-3-buthylimidazolium acetate. Moreover, in the case of ammonium ionic liquids, even though they have comparable potential to dissolve cellulose, it was impossible to depolymerize lignocellulose and extract lignin. Furthermore, they did not improve the efficiency of the hydrolysis process, which in turn led to low alcohol concentration. Overall, from the presented results, it can be assumed that the stinging nettle stems are a very promising bioenergy crop.

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Electrospun Silk-Cellulose Composite Nanomaterials Using Ionic Liquid Regenerated Films

Proceedings ◽

10.3390/cgpm2020-07597 ◽

2020 ◽

Vol 69 (1) ◽

pp. 31

Author(s):

Ashley Rivera-Galletti ◽

Ye Xue ◽

Stacy Love ◽

David Salas de la Cruz ◽

Xiao Hu

Keyword(s):

Ionic Liquid ◽

Ionic Liquids ◽

Organic Solvents ◽

Raw Materials ◽

Composite Films ◽

Structural Defects ◽

Composite Nanomaterials ◽

Cellulose Derivatives ◽

Cellulose Content ◽

Cellulose Nanomaterials

Electrospinning is a widely used technique to draw recalcitrant biopolymer solutions into micro to nanoscale materials in a simple and economical way. The first focus of this research involved using ionic liquids as a non-volatile solvent for natural insoluble biopolymers such as silk and cellulose (or cellulose derivatives). Compared to traditional organic solvents, ionic liquids can dissolve biopolymers without altering the molecular weight of the biopolymer. In this study, 1-ethyl-3-methylimidizolium acetate (EMIMAc) ionic liquid was used and the regenerated films were coagulated in baths of EtOH or water. The second focus of this research explored the dissolution of IL-regenerated composites into organic solvents and their electrospun composite nanomaterials. Various ratios of silk-cellulose bio-composite films regenerated from ionic liquids were used as the raw materials and sequentially dissolved/dispersed into a Formic Acid-CaCl2 solution in order to initiate the electrospinning of silk-cellulose nanomaterials. Because of the variability of ionic liquids, the nanomaterials produced using this technique have unique and tunable properties such as large surface area to volume ratios and low structural defects. FTIR and SEM results suggest that the structure and morphology of the final nanosized samples becomes more globular when the biopolymer composition ratio has increased cellulose content. TGA results demonstrated that the electrospun materials have better thermal stability than the original films. This two-step electrospinning method, using ionic liquid as a non-volatile solvent to first dissolve and mix raw natural materials, may lead to extensive research into its biomedical and pharmaceutical applications in the future.

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Computational solvation analysis of biomolecules in aqueous ionic liquid mixtures

Biophysical Reviews ◽

10.1007/s12551-018-0416-5 ◽

2018 ◽

Vol 10 (3) ◽

pp. 825-840 ◽

Cited By ~ 9

Author(s):

Veronika Zeindlhofer ◽

Christian Schröder

Keyword(s):

Ionic Liquid ◽

Ionic Liquids ◽

Liquid Mixtures ◽

High Viscosity ◽

Full Potential ◽

New Class ◽

Fundamental Knowledge ◽

Structure And Dynamics ◽

Significant Interest ◽

The Impact

Abstract Based on their tunable properties, ionic liquids attracted significant interest to replace conventional, organic solvents in biomolecular applications. Following a Gartner cycle, the expectations on this new class of solvents dropped after the initial hype due to the high viscosity, hydrolysis, and toxicity problems as well as their high cost. Since not all possible combinations of cations and anions can be tested experimentally, fundamental knowledge on the interaction of the ionic liquid ions with water and with biomolecules is mandatory to optimize the solvation behavior, the biodegradability, and the costs of the ionic liquid. Here, we report on current computational approaches to characterize the impact of the ionic liquid ions on the structure and dynamics of the biomolecule and its solvation layer to explore the full potential of ionic liquids.

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