Phase Structure of Acrylic Fibers Processed with Ionic Liquid as Solvent

2012 ◽  
Vol 560-561 ◽  
pp. 41-45 ◽  
Author(s):  
Xue Min Yin ◽  
Li Zhang ◽  
Xin Jun Zhu ◽  
Hua Ping Wang ◽  
Yu Mei Zhang
Keyword(s):  
Ionic Liquid ◽  
Phase Structure ◽  
Draw Ratio ◽  
High Viscosity ◽  
Wet Spinning ◽  
Ordered Structure ◽  
Strain Measurements ◽  
Initial Modulus ◽  
Paracrystalline Structure ◽  
Acrylic Fibers

The acrylic fibers were prepared by dry-jet wet spinning technology from polyacrylinitrile (PAN) /1-butyl-3-methylimidazolium chloride ([BMIM]Cl) solution for the investigation of phase structure changing with drawing in boiling water. The DMA, WAXD and stress-strain measurements were conducted. It is shown that only a single Tg was observed from DMA and the paracrystalline structure was shown from WAXD. Although the the crystallinity and orientation increased with increasing draw ratio, the high crystallinity of the pre-drawn fiber indicates that the ordered structure was formed in the pre-drawn fiber by the high pre-drawn ratio (3.5) during the dry-jet wet spinning from high-viscosity PAN/[BMIM]Cl solution. It is also found that the initial modulus, ultimate elongation and tenacity increased with the increase of draw ratio.

scholarly journals Modification of Chitin Particles with Ionic Liquids Containing Ethyl Substituent in a Cation

2017 ◽  
Vol 2017 ◽  
pp. 1-9 ◽  
Author(s):  
Malgorzata M. Jaworska ◽  
Andrzej Górak ◽  
Joanna Zdunek
Keyword(s):  
Particle Size ◽  
Ionic Liquid ◽  
Ionic Liquids ◽  
Hydrogen Bonds ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
High Viscosity ◽  
Physical Structure ◽  
Ethyl Group ◽  
Network Of Hydrogen Bonds

Chitin cannot be dissolved in conventional solvents due to the strong inter- and intrasheet network of hydrogen bonds and the large number of crystalline regions. Some ionic liquids (ILs) have been suggested in the literature as possible solvents for chitin. Seven of them, all having an ethyl group as substituent in the cationic ring, have been tested in this work: [Emim][Cl], [Emim][Br], [Emim][I], [Emim][OAc], [Emim][Lact], [Epyr][I], and [EMS][BFSI]. Chitin was insoluble in [EMS][BFSI] while for all other ILs solubility was limited due to high viscosity of solutions and equilibria have not been reached. Changes in physical structure, particle size distribution, and crystallinity of recovered chitin depended on ionic liquid used. Increase in porosity was observed for chitin treated with [Emim][Cl], [Emim][I], [Emim][Br], and [Emim][Lact]; changes in particle size distribution were observed for [Emim][AcOH] and [EMS][BFSI]; increase in crystallinity was noticed for chitin treated with [Epyr][I] while decrease in crystallinity for [Emim][I] was noticed. All tested ionic liquids were reused four times and changes in FTIR spectra could be observed for each IL.

Effect of Ionic Liquid on the Properties of Nanocomposites Based on Epoxy/CNT Hardened with MCDEA

2021 ◽  
Vol 1165 ◽  
pp. 31-38
Author(s):  
Danielle Ferreira dos Santos ◽  
Bluma Guenther Soares
Keyword(s):  
Ionic Liquid ◽  
High Performance ◽  
High Viscosity ◽  
Van Der Waals Interactions ◽  
Great Tendency ◽  
Excellent Performance ◽  
Rigid System ◽  
Dispersion Agent ◽  
Thermal And Electrical Properties ◽  
Diethyl Phosphate

Thermosetting systems based on epoxy resin (RE) with the dispersion of carbon nanotubes (CNT), have been extensively studied by the development of high-performance materials with interesting mechanical, thermal and electrical properties that the thermo-rigid system achieves with the addition of CNT, and thus contribute to obtain composites with excellent performance in low amounts of this filler. However, ensuring a good dispersion of these systems is not easy, as CNTs have a great tendency to cluster due to Van der Waals interactions. To assist in the dispersion of the systems, a phosphonium-based ionic liquid, tributyl (ethyl) -phosphonium diethyl phosphate, acted with a double role, as a dispersion agent and catalyst in systems hardened with MCDEA (4,4’-methylenebis (3 - chloro-2,6-diethylaniline), which is a solid compound giving the systems high viscosity, and with the addition of LI improved the dispersion of the systems, as well as the processability in the preparation of the nanocomposites.

The Effect of the Mixture Composition of BmimBF4-Acetonitrile on the Excited State Relaxation Dynamics of a Solar Cell Dye D149: An Ultrafast Transient Absorption Study

2021 ◽  
Author(s):  
Nishith Maity ◽  
Piotr Piatkowski ◽  
Kamil Polok ◽  
Francois-Alexandre Miannay ◽  
Abdenacer Idrissi
Keyword(s):  
Ionic Liquid ◽  
Excited State ◽  
Solar Cell ◽  
Transient Absorption ◽  
Excited Electronic State ◽  
Relaxation Times ◽  
High Viscosity ◽  
Mixture Composition ◽  
Gradual Change ◽  
The One

It has been recognized that the understanding of the photo physic of the dyes used in solar cells in an important step in improving their efficiency. Certainly using ionic liquid as an electrolyte is a good solution as it stabilizes the excited state of the dye, however, because of the high viscosity, the diffusion of the components of the solar cell (dye, electrolyte, the chosen redox couple) is very low and has consequences on the other processes (Forward and backward processes). One of the ideas, is to modulate the viscosity of the ionic liquid by mixing the ionic liquid with a solvent. The goal then of this work is to quantify the mixture composition dependence of the excited state relaxation times. Other studies should be carried out to quantify the mixture dependence on the time characteristics of other processes (charge injection, collection etc.) to optimize the working optimal conditions of the solar cell. Following this goal, the present study is devoted to characterize the relaxation time of in the whole mixture composition of BmimBF4 and acetonitrile and in the neat components. For the first time, the decay relaxation times of the first excited electronic state of D149 dye, as obtained by transient absorption spectroscopy (TAS). These relaxation times are monitored by a gradual change of the local structure around a dye, from the one dominated by the interionic interactions, high viscosity and low polarity (as quantified by the static dielectric constant) in BmimBF4 to the one that is dominated by dipole-dipole interactions, low viscosity and high polarity in acetonitrile.<br>

scholarly journals Mass transport and yield during spinning of lignin-cellulose carbon fiber precursors

Holzforschung ◽  
2019 ◽  
Vol 73 (5) ◽  
pp. 509-516 ◽  
Author(s):  
Jenny Bengtsson ◽  
Kerstin Jedvert ◽  
Artur Hedlund ◽  
Tobias Köhnke ◽  
Hans Theliander
Keyword(s):  
Ionic Liquid ◽  
Mass Transport ◽  
Total Concentration ◽  
Renewable Resource ◽  
Wet Spinning ◽  
Lignin Concentration ◽  
Liquid Solutions ◽  
Fundamental Understanding ◽  
Crucial Information ◽  
Soluble Lignin

Abstract Lignin, a substance considered as a residue in biomass and ethanol production, has been identified as a renewable resource suitable for making inexpensive carbon fibers (CFs), which would widen the range of possible applications for light-weight CFs reinforced composites. Wet spinning of lignin-cellulose ionic liquid solutions is a promising method for producing lignin-based CFs precursors. However, wet-spinning solutions containing lignin pose technical challenges that have to be solved to enable industrialization. One of these issues is that a part of the lignin leaches into the coagulation liquid, which reduces yield and might complicate solvent recovery. In this work, the mass transport during coagulation is studied in depth using a model system and trends are confirmed with spinning trials. It was discovered that during coagulation, efflux of ionic liquid is not hindered by lignin concentration in solution and the formed cellulose network will enclose soluble lignin. Consequently, a high total concentration of lignin and cellulose in solution is advantageous to maximize yield. This work provides a fundamental understanding on mass transport during coagulation of lignin-cellulose solutions, crucial information when designing new solution-based fiber forming processes.

Manipulating ordered structure of ionic liquid crystalline polymers through tuning the alkyl spacer length

Polymer ◽  
2014 ◽  
Vol 55 (25) ◽  
pp. 6504-6512 ◽  
Author(s):  
Jiao-Jiao Yan ◽  
He-Lou Xie ◽  
Liang Weng ◽  
Shuang Yang ◽  
Hai-Liang Zhang
Keyword(s):  
Ionic Liquid ◽  
Liquid Crystalline ◽  
Liquid Crystalline Polymers ◽  
Ordered Structure ◽  
Spacer Length ◽  
Crystalline Polymers

Understanding key wet spinning parameters in an ionic liquid spun regenerated cellulosic fibre

Cellulose ◽  
2016 ◽  
Vol 23 (4) ◽  
pp. 2741-2751 ◽  
Author(s):  
Rasike De Silva ◽  
Kylie Vongsanga ◽  
Xungai Wang ◽  
Nolene Byrne
Keyword(s):  
Ionic Liquid ◽  
Wet Spinning ◽  
Cellulosic Fibre

scholarly journals Nanostructure of the H-terminated p-Si(111)/ionic liquid interface and the effect of added lithium salt

2017 ◽  
Vol 19 (1) ◽  
pp. 54-58 ◽  
Author(s):  
Viktor Hoffmann ◽  
Abhishek Lahiri ◽  
Natalia Borisenko ◽  
Timo Carstens ◽  
Giridhar Pulletikurthi ◽  
...  
Keyword(s):  
Ionic Liquid ◽  
Lithium Salt ◽  
Liquid Interface ◽  
Ordered Structure

AFM images of the ionic liquid/H-terminated p-Si(111) interface showing an ordered structure of 3.8 nm in size.

Influence of draw ratio on the structure and properties of PEDOT-PSS/PAN composite conductive fibers

RSC Advances ◽  
2014 ◽  
Vol 4 (76) ◽  
pp. 40385-40389 ◽  
Author(s):  
Xin Li ◽  
Yin Liu ◽  
Zhenghao Shi ◽  
Congju Li ◽  
Guangming Chen
Keyword(s):  
Sulfonic Acid ◽  
Draw Ratio ◽  
Wet Spinning ◽  
Structure And Properties ◽  
Polystyrene Sulfonic Acid ◽  
Conductive Fibers

Composite conductive fibers based on poly(3,4-ethylenedioxythiophene)-polystyrene sulfonic acid (PEDOT-PSS) solution blended with polyacrylonitrile (PAN) were obtained via wet spinning.

Layering of ionic liquids on rough surfaces

Nanoscale ◽  
2016 ◽  
Vol 8 (7) ◽  
pp. 4094-4106 ◽  
Author(s):  
Alexis Sheehan ◽  
L. Andres Jurado ◽  
Shivaprakash N. Ramakrishna ◽  
Andrea Arcifa ◽  
Antonella Rossi ◽  
...  
Keyword(s):  
Ionic Liquid ◽  
Ionic Liquids ◽  
Rough Surfaces ◽  
Ordered Structure ◽  
Structural Forces ◽  
Rough Interfaces ◽  
Nanoscale Roughness

Structural forces reveal the ordered structure of one ionic liquid at rough interfaces of well-defined nanoscale roughness, also under nanoconfinement.

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