44 research outputs found

    3-(1-Methyl-3-imidazolio)propane­sulfonate: a precursor to a Brønsted acid ionic liquid

    Get PDF
    The title compound, C7H12N2O3S, is a zwitterion precursor to a Brønsted acid ionic liquid with potential as an acid catalyst. The C—N—C—C torsion angle of 100.05 (8)° allows the positively charged imidazolium head group and the negatively charged sulfonate group to inter­act with neighboring zwitterions, forming a C—H⋯O hydrogen-bonding network; the shortest among these inter­actions is 2.9512 (9) Å. The C—H⋯O inter­actions can be described by graph-set notation as two R 2 2(16) and one R 2 2(5) hydrogen-bonded rings

    Char-forming behavior of nanofibrillated cellulose treated with \u3ci\u3eglycidyl phenyl\u3c/i\u3e POSS

    Get PDF
    Cellulose-reinforced composites have received much attention due to their structural reinforcing, light weight, biodegradable, non-toxic, low cost and recyclable characteristics. However, the tendency for cellulose to aggregate and its poor dispersion in many polymers, such as polystyrene, continues to be one of the most challenging roadblocks to large scale production and use of cellulose-polymer composites. In this study, nanofibrillated cellulose (NFC) is modified using GlycidylPhenyl-POSS (a polyhedral oligomeric silsesquioxane). The product yield, morphology, and crystallinity are characterized using a variety of spectroscopy and microscopy techniques. Thermal analyses are performed using thermal gravimetric analysis and pyrolysis combustion flow calorimetry

    Ionic liquids-based processing of electrically conducting chitin nanocomposite scaffolds for stem cell growth

    Get PDF
    In the present study, we have successfully combined the biocompatible properties of chitin with the high electrical conductivity of carbon nanotubes (CNTs) by mixing them using an imidazolium-based ionic liquid as a common solvent/dispersion medium. The resulting nanocomposites demonstrated uniform distribution of CNTs, as shown by scanning electron microscopy (SEM) and optical microscopy. Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction confirmed the α-crystal structure of chitin in the regenerated chitin nanocomposite scaffolds. Increased CNT concentration in the chitin matrix resulted in higher conductivity of the scaffolds. Human mesenchymal stem cells adhered to, and proliferated on, chitin/CNT nanocomposites with different ratios. Cell growth in the first 3 days was similar on all composites at a range of (0.01 to 0.07) mass fraction of CNT. However, composites at 0.1 mass fraction of CNT showed reduced cell attachment. There was a significant increase in cell proliferation using 0.07 mass fraction CNT composites suggesting a stem cell enhancing function for CNTs at this concentration. In conclusion, ionic liquid allowed the uniform dispersion of CNTs and dissolution of chitin to create a biocompatible, electrically conducting scaffold permissive for mesenchymal stem cell function. This method will enable the fabrication of chitin- based advanced multifunctional biocompatible scaffolds where electrical conduction is critical for tissue function

    SISGR: Linking Ion Solvation and Lithium Battery Electrolyte Properties

    No full text
    The solvation and phase behavior of the model battery electrolyte salt lithium trifluoromethanesulfonate (LiCF3SO3) in commonly used organic solvents; ethylene carbonate (EC), gamma-butyrolactone (GBL), and propylene carbonate (PC) was explored. Data from differential scanning calorimetry (DSC), Raman spectroscopy, and X-ray diffraction were correlated to provide insight into the solvation states present within a sample mixture. Data from DSC analyses allowed the construction of phase diagrams for each solvent system. Raman spectroscopy enabled the determination of specific solvation states present within a solvent-ÃÂÃÂsalt mixture, and X-ray diffraction data provided exact information concerning the structure of a solvates that could be isolated Thermal analysis of the various solvent-salt mixtures revealed the phase behavior of the model electrolytes was strongly dependent on solvent symmetry. The point groups of the solvents were (in order from high to low symmetry): C2V for EC, CS for GBL, and C1 for PC(R). The low symmetry solvents exhibited a crystallinity gap that increased as solvent symmetry decreased; no gap was observed for EC-LiTf, while a crystallinity gap was observed spanning 0.15 to 0.3 mole fraction for GBL-LiTf, and 0.1 to 0.33 mole fraction for PC(R)-LiTf mixtures. Raman analysis demonstrated the dominance of aggregated species in almost all solvent compositions. The AGG and CIP solvates represent the majority of the species in solutions for the more concentrated mixtures, and only in very dilute compositions does the SSIP solvate exist in significant amounts. Thus, the poor charge transport characteristics of CIP and AGG account for the low conductivity and transport properties of LiTf and explain why is a poor choice as a source of Li+ ions in a Li-ion battery

    Density, Viscosity, Speed of Sound, Bulk Modulus, and Surface Tension of Binary Mixtures of <i>n</i>‑Heptane + 2,2,4-Trimethylpentane at (293.15 to 338.15) K and 0.1 MPa

    No full text
    In this work, the physical properties of binary mixtures of <i>n</i>-heptane and 2,2,4-trimethylpentane were measured. Density and speed of sound were measured at temperatures ranging from (293.15 to 338.15) K, and viscosity was measured at temperatures ranging from (293.15 to 333.15) K. At 298.15 K, pure component values for heptane of 679.61 kg·m<sup>–3</sup>, 0.389 mPa·s, and 1130.1 m·s<sup>–1</sup> for density, viscosity, and speed of sound, respectively, agree with literature values. Similarly for 2,2,4-trimethylpentane, the values of 687.70 kg·m<sup>–3</sup>, 0.501 mPa·s, and 1081.7 m·s<sup>–1</sup> for density, viscosity, and speed of sound, respectively, agree with literature values. Density mole fraction and temperature data were fit to a second-order polynomial. Bulk moduli ranged from (551.7 to 907.1) MPa over (293.15 to 338.15) K. Viscosity mole fraction data were fit using the three-body McAllister model, while the viscosity deviations were fit to a Redlich–Kister type equation. For the mixtures, an increase in mole fraction of 2,2,4-trimethylpentane resulted in an increase in density and viscosity and in a decrease in speed of sound, bulk modulus, and surface tension. Increases in temperature decreased density, viscosity, speed of sound, and bulk modulus. At room temperature, the surface tension values ranged from (18.7 to 20.3) mN·m<sup>–1</sup>. These data can be used by researchers who are modeling the combustion process of mixtures of primary reference fuels and are modeling the physical properties of fuels
    corecore