TY  - JOUR
A1  - Strehmel, Veronika
A1  - Berdzinski, Stefan
A1  - Strauch, Peter
A1  - Hoffmann-Jacobsen, Kerstin
A1  - Strehmel, Bernd
T1  - Investigation of molecular solvents and ionic liquids with a dual probe
JF  - Zeitschrift für physikalische Chemie : international journal of research in physical chemistry and chemical physics
N2  - A dual probe was investigated by UV-Vis, fluorescence, and ESR spectroscopy. It comprises the pyrene chromophore and the paramagnetic 2,2,6,6-tetramethylpiperidinyl-N-oxyl radical that are covalently linked together via an ester bridge. The dual probe was used to investigate molecular solvents of different polarity as well as ionic liquids bearing either imidazolium or pyrrolidinium cations and various anions, such as bis(trifluoromethylsulfonyl)imide, tetrafluoroborate, tris(pentafluoroethyl)trifluorophosphate, or dicyanamide. The dual probe does not show solvatochromism that is typical for some pyrenes. Furthermore, the dual probe is considerable less mobile compared to 2,2,6,6-tetramethylpiperidinyl-N-oxyl (TEMPO) without additional substituent as detected by ESR spectroscopy. This is caused by the bulky pyrenyl substituent bound at the dual probe resulting in a reduced mobility of the dual probe.
KW  - Ionic Liquid
KW  - Fluorescence
KW  - ESR
KW  - Molecular Probe
Y1  - 2014
U6  - https://doi.org/10.1515/zpch-2014-0453
SN  - 0942-9352
VL  - 228
IS  - 2-3
SP  - 155
EP  - 169
PB  - De Gruyter
CY  - Berlin
ER  - 
TY  - JOUR
A1  - Bagdahn, Christian
A1  - Taubert, Andreas
T1  - Ionogel fiber mats - functional materials via electrospinning of PMMA and the ionic liquid bis(1-butyl-3-methyl-imidazolium) Tetrachloridocuprate(II), [Bmim](2)[CuCl4]
JF  - Zeitschrift für Naturforschung : B, Chemical sciences
N2  - Ionogel fiber mats were made by electrospinning poly(methylmethacrylate) (PMMA) and the ionic liquid (IL) bis(1-butyl-3-methyl-imidazolium) tetrachloridocupraten, [Bmim](2)[CuCl4], from acetone. The morphology of the electrospun ionogels strongly depends on the spinning parameters. Dense and uniform fiber mats were only obtained at concentrations of 60 to 70 g of polymer and IL mass combined. Lower concentrations led to a low number of poorly defined fibers. High voltages of 20 to 25 kV led to well-defined and uniform fibers; voltages between 15 and 20 kV again led to less uniform and less dense fibers. At 10 kV and lower, no spinning could be induced. Finally, PMMA fibers electrospun without IL show a less well-defined morphology combining fibers and oblong droplets indicating that the IL has a beneficial effect on the electrospinning process. The resulting materials are prototypes for new functional materials, for example in sterile filtration.
KW  - Ionic Liquid
KW  - Ionogel
KW  - Electrospinning
KW  - Fiber
KW  - Hydrogen Production
KW  - Filtration
Y1  - 2013
U6  - https://doi.org/10.5560/ZNB.2013-3195
SN  - 0932-0776
SN  - 1865-7117
VL  - 68
IS  - 10
SP  - 1163
EP  - 1171
PB  - De Gruyter
CY  - Tübingen
ER  -