Wenjian+Du+log

Wenjian Du log In SMILE. @ means R, @@ means S. Peggy Dominy X2754 dominymf@drexel.edu

Richard P. Swatloski, Scott K. Spear, John D. Holbrey, Robin D. Rogers. Dissolution of cellulose with ionic liquids, J. AM. CHEM. SOC. 2002, 124, 4974-4975. [|doi: 10.1021/ja025790m]
 * [Full Marks JCB]**

Cellulose has potential in many different areas.

Because cellulose is insoluble in common solvents, including water, so although cellulose has almost infinite resource in nature and people have great interest in it, most research about it are not green.

The first chemical could use to dissolve cellulose is molten N-ethylpyridinium chloride, but due to a relatively high melting point (118 C), this seem not practical. We are trying to use ionic liquid (ILs) to dissolve cellulose and study the influence of combination of ILs on solution efficiency.

Ionic liquids we used here are combination of cations such like 1-butyl-3-methylimidazolium (C4mim), C6 mim and C8 mim, and anions such like Cl-, Br-. [SCN]-, and [BF4]-. We dissolve cellulose in ionic liquids.

Cellulose is not soluble in ILs when temperature is room temperature but soluble in most of ILs when temperature is increased to 100-110 C.

Heating samples by microwave will not only improve dissolution rate of cellulose, but also will make the decomposition of cellulose more easily.

Using ILs which has Cl- as an anion, we could dissolve up to 25 wt% cellulose. It is more preferred that the concentration is higher than 10%, because they will keep the anisotropy of material which will enhance mechanical properties.

Cellulose molecules could be separated after the intramolecular hydrogen-bonding network has beed broken. [C4min]Cl has a higher chloride concentration (20 mol%) than LiCl/DMAC solution (6.7 mol%).

The higher Cl- concentration, the easier and the larger amount of the dissolution of cellulose will be. But the longer length of cations in ILs will not be as effective as shorter length cations when dissolve cellulose.

Water in ILs will significantly reduce the solubility of cellulose due to the hydrogen bonding of water to cellulose microfibers.

By adding water, ethanol, or acetone, we could precipitate cellulose from ILs and control the morphology of cellulose participated from solution.

By many characterization methods we found that the morphology of cellulose of the regenerated material is greatly changed.

From the TGA curve, we found that cellulose will decompose at temperature from 350 to 360 C, which is lower than the initial material, but gives a higher char yield.

In this paper, we found that ILs can be a good solvent for dissolving cellulose, especially when the inions are strong electron accepters like Cl-.

FAQ: Excepts those spectra sourses which already been posted in 2010 FAQ, I found these sources for IR spectra: 1. [|FDM Reference Spectra Databases]: A database maintained by Fiveash Data Management, Inc. 2. [|AEDC/EPA spectral database]: This database was under the cooperation of the Environmental Protection Agency Office of Air Quality Planning and Standards (EPA/OAQPS) and the US Air Force. 3. [|David Sullivan FT-IR Library]: By David Sullivan. Last updated on 18 April 1998. 4. [|Ivo Leito's FT-IR spectra of paint and coating materials] : This database foucus on conservation and painting-related materials (pigments, binders, fillers, etc). 5. [|NICODOM databases]:

Spectra FAQ problem from 2010. __**"**__ __**NIST Chemistry WebBook**__ [] - This source provides IR, THz IR, Mass, and UV-Vis spectra, tabulations of data from GC spectra, and serveral physical, chemical, and thermodynamic properties of chemicals. The service allows a user to search for information by inputting chemical formulas, chemical names, IUPAC identifiers, CAS registry numbers, reactions, chemical structures, and authors of publications in the NIST database.

__**Spectral Database for Organic Compounds**__ [] - This source is a database for organic compounds that provides MS, 13C NMR, 1H NMR, IR, Raman, and ESR spectra. The source allows a user to search for a chemical by its compound name, molecular formula, molecular weight, CAS registry number, and SDBS number.

__**Sigma-Aldrich**__ [] - This source provides FT-NMR, FT-IR Raman, and FT-IR condensed phase spectra for certain chemical products. The source also provides MSDS sheets for chemicals and allows a user to search for a chemical by inputting a chemical name or by drawing a chemical structure in a java application.

__**NMRShiftDB**__ [] - This source is a database for organic compounds that provides 13C NMR, 1H NMR, and other types of NMR spectra. The database also allows for NMR spectrum prediction for a file containing a chemical structure on a user's computer. The database is open source and features peer-reviewed submission of sets of data. The database allows a user to search for a chemical by inputting the chemical name, the chemical structure, and various other properties and also allows a user to search for a specific chemical spectrum.

__**ChemSpider**__ [] - This source is a database for all types of chemicals (organic, inorganic, biomolecules etc...) that provides NMR, IR, UV-Vis, and other experimental spectra for certain chemicals. The service also provides experimental and predicted physical and chemical properties. The database allows users to search for a chemical by inputting the chemical name, trade name, registry number, SMILES, InChI, CSID, and by drawing the chemical structure. Users can also upload spectra for specific molecules.

-Paul DeGregory"