TY  - JOUR
A1  - Zehbe, Rolf
A1  - Zehbe, Kerstin
T1  - Strontium doped poly-epsilon-caprolactone composite scaffolds made by reactive foaming
JF  - The European journal of the history of economic thought
N2  - In the reconstruction and regeneration of bone tissue, a primary goal is to initiate bone growth and to stabilize the surrounding bone. In this regard, a potentially useful component in biomaterials for bone tissue engineering is strontium, which acts as cationic active agent, triggering certain intracellular pathways and acting as so called dual action bone agent which inhibits bone resorption while stimulating bone regeneration. In this study we established a novel processing for the foaming of a polymer (poly-epsilon-caprolactone) and simultaneous chemical reaction of a mixture of calcium and strontium hydroxides to the respective carbonates using supercritical carbon dioxide. The resultant porous composite scaffold was optimized in composition and strontium content and was characterized via different spectroscopic (infrared and Raman spectroscopy, energy dispersive X-ray spectroscopy), imaging (SEM, mu CT), mechanical testing and in vitro methods (fluorescence vital staining, MTT-assay). As a result, the composite scaffold showed good in vitro biocompatibility with partly open pore structure and the expected chemistry. First mechanical testing results indicate sufficient mechanical stability to support future in vivo applications. (C) 2016 Elsevier B.V. All rights reserved.
KW  - Strontium
KW  - Poly-epsilon-caprolactone
KW  - Porous scaffold
KW  - CAL-72 osteoblasts
KW  - L-929 fibroblasts
KW  - Reactive foaming
KW  - mu CT imaging
KW  - Spectroscopy
Y1  - 2016
U6  - https://doi.org/10.1016/j.msec.2016.05.045
SN  - 0928-4931
SN  - 1873-0191
VL  - 67
SP  - 259
EP  - 266
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Thiel, Kerstin
A1  - Zehbe, Rolf
A1  - Roesner, Jerômé
A1  - Strauch, Peter
A1  - Enthaler, Stephan
A1  - Thomas, Arne
T1  - A polymer analogous reaction for the formation of imidazolium and NHC based porous polymer networks
N2  - A polymer analogous reaction was carried out to generate a porous polymeric network with N-heterocyclic carbenes (NHC) in the polymer backbone. Using a stepwise approach, first a polyimine network is formed by polymerization of the tetrafunctional amine tetrakis(4-aminophenyl)methane. This polyimine network is converted in the second step into polyimidazolium chloride and finally to a polyNHC network. Furthermore a porous Cu(II)-coordinated polyNHC network can be generated. Supercritical drying generates polymer networks with high permanent surface areas and porosities which can be applied for different catalytic reactions. The catalytic properties were demonstrated for example in the activation of CO2 or in the deoxygenation of sulfoxides to the corresponding sulfides.
Y1  - 2013
UR  - http://pubs.rsc.org/en/content/articlepdf/2013/py/c2py20947k
U6  - https://doi.org/10.1039/C2PY20947K
ER  - 
TY  - JOUR
A1  - Thiel, Kerstin
A1  - Zehbe, Rolf
A1  - Röser, Jerome
A1  - Strauch, Peter
A1  - Enthaler, Stephan
A1  - Thomas, Arne
T1  - A polymer analogous reaction for the formation of imidazolium and NHC based porous polymer networks
JF  - Polymer Chemistry
N2  - A polymer analogous reaction was carried out to generate a porous polymeric network with N-heterocyclic carbenes (NHC) in the polymer backbone. Using a stepwise approach, first a polyimine network is formed by polymerization of the tetrafunctional amine tetrakis(4-aminophenyl)methane. This polyimine network is converted in the second step into polyimidazolium chloride and finally to a polyNHC network. Furthermore a porous Cu(II)-coordinated polyNHC network can be generated. Supercritical drying generates polymer networks with high permanent surface areas and porosities which can be applied for different catalytic reactions. The catalytic properties were demonstrated for example in the activation of CO2 or in the deoxygenation of sulfoxides to the corresponding sulfides.
Y1  - 2013
U6  - https://doi.org/10.1039/c2py20947k
SN  - 1759-9954
VL  - 4
IS  - 6
SP  - 1848
EP  - 1856
PB  - Royal Society of Chemistry
CY  - Cambridge
ER  - 
TY  - JOUR
A1  - Zehbe, Kerstin
A1  - Kollosche, Matthias
A1  - Lardong, Sebastian
A1  - Kelling, Alexandra
A1  - Schilde, Uwe
A1  - Taubert, Andreas
T1  - Ionogels Based on Poly(methyl methacrylate) and Metal-Containing Ionic Liquids: Correlation between Structure and Mechanical and Electrical Properties
JF  - International journal of molecular sciences
N2  - Ionogels (IGs) based on poly(methyl methacrylate) (PMMA) and the metal-containing ionic liquids (ILs) bis-1-butyl-3-methlimidazolium tetrachloridocuprate(II), tetrachloride cobaltate(II), and tetrachlorido manganate(II) have been synthesized and their mechanical and electrical properties have been correlated with their microstructure. Unlike many previous examples, the current IGs show a decreasing stability in stress-strain experiments on increasing IL fractions. The conductivities of the current IGs are lower than those observed in similar examples in the literature. Both effects are caused by a two-phase structure with micrometer-sized IL-rich domains homogeneously dispersed an IL-deficient continuous PMMA phase. This study demonstrates that the IL-polymer miscibility and the morphology of the IGs are key parameters to control the (macroscopic) properties of IGs.
KW  - microstructure
KW  - ionogels
KW  - ionic liquids
KW  - phase separation
KW  - mechanical properties
KW  - ionic conductivity
Y1  - 2016
U6  - https://doi.org/10.3390/ijms17030391
SN  - 1422-0067
VL  - 17
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Zehbe, Kerstin
A1  - Lange, Alyna
A1  - Taubert, Andreas
T1  - Stereolithography Provides Access to 3D Printed lonogels with High Ionic Conductivity
JF  - Energy Fuels
N2  - New ionogels (IGs) were prepared by combination of a series of sulfonate-based ionic liquids (ILs), 1-methyl-3-(4-sulfobutyl)imidazolium para-toluenesulfonate [BmimSO(3)][pTS], 1-methyl-1-butylpiperidiniumsulfonate para-toluenesul-fonate [BmpipSO(3)] [pTS], and 1-methyl-3-(4-sulfobutyl) imidazolium methylsulfonate [BmimSO(3)H][MeSO3] with a commercial stereolithography photoreactive resin. The article describes both the fundamental properties of the ILs and the resulting IGs. The IGs obtained from the ILs and the resin show high ionic conductivity of up to ca. 0.7.10(-4) S/cm at room temperature and 3.4-10(-3) S/cm at 90 degrees C. Moreover, the IGs are thermally stable to about 200 degrees C and mechanically robust. Finally, and most importantly, the article demonstrates that the IGs can be molded three-dimensionally using stereolithography. This provides, for the first time, access to IGs with complex 3D shapes with potential application in battery or fuel cell technology.
Y1  - 2019
U6  - https://doi.org/10.1021/acs.energyfuels.9b03379
SN  - 0887-0624
SN  - 1520-5029
VL  - 33
IS  - 12
SP  - 12885
EP  - 12893
PB  - American Chemical Society
CY  - Washington
ER  - 
TY  - JOUR
A1  - Pereira, Rui F. P.
A1  - Zehbe, Kerstin
A1  - Günter, Christina
A1  - dos Santos, Tiago
A1  - Nunes, Silvia C.
A1  - Almeida Paz, Filipe A.
A1  - Silva, Maria M.
A1  - Granja, Pedro L.
A1  - Taubert, Andreas
A1  - de Zea Bermudez, Verónica
T1  - Ionic liquid-assisted synthesis of mesoporous silk fibroin/silica hybrids for biomedical applications
JF  - ACS Omega
N2  - New mesoporous silk fibroin (SF)/silica hybrids were processed via a one-pot soft and energy-efficient sol-gel chemistry and self-assembly from a silica precursor, an acidic or basic catalyst, and the ionic liquid 1-butyl-3-methylimidazolium chloride, acting as both solvent and mesoporosity-inducer. The as-prepared materials were obtained as slightly transparent-opaque, amorphous monoliths, easily transformed into powders, and stable up to ca. 300 degrees C. Structural data suggest the formation of a hexagonal mesostructure with low range order and apparent surface areas, pore volumes, and pore radii of 205-263 m(2) g(-1), 0.16-0.19 cm(3) g(-1), and 1.2-1.6 nm, respectively. In all samples, the dominating conformation of the SF chains is the beta-sheet. Cytotoxicity/bioactivity resazurin assays and fluorescence microscopy demonstrate the high viability of MC3T3 pre-osteoblasts to indirect (>= 99 +/- 9%) and direct (78 +/- 2 to 99 +/- 13%) contact with the SF/silica materials. Considering their properties and further improvements, these systems are promising candidates to be explored in bone tissue engineering. They also offer excellent prospects as electrolytes for solid-state electrochemical devices, in particular for fuel cells.
Y1  - 2018
U6  - https://doi.org/10.1021/acsomega.8b02051
SN  - 2470-1343
VL  - 3
IS  - 9
SP  - 10811
EP  - 10822
PB  - American Chemical Society
CY  - Washington
ER  - 
TY  - JOUR
A1  - Balischewski, Christian
A1  - Behrens, Karsten
A1  - Zehbe, Kerstin
A1  - Günter, Christina
A1  - Mies, Stefan
A1  - Sperlich, Eric
A1  - Kelling, Alexandra
A1  - Taubert, Andreas
T1  - Ionic liquids with more than one metal
BT  - optical and rlectrochemical properties versus d-block metal vombinations
JF  - Chemistry - a European journal
N2  - Thirteen N-butylpyridinium salts, including three monometallic [C4Py](2)[MCl4], nine bimetallic [C4Py](2)[(M1-xMxCl4)-M-a-Cl-b] and one trimetallic compound [C4Py](2)[(M1-y-zMyMz (c) Cl4)-M-a-M-b] (M=Co, Cu, Mn; x=0.25, 0.50 or 0.75 and y=z=0.33), were synthesized and their structure and thermal and electrochemical properties were studied. All compounds are ionic liquids (ILs) with melting points between 69 and 93 degrees C. X-ray diffraction proves that all ILs are isostructural. The conductivity at room temperature is between 10(-4) and 10(-8) S cm(-1). Some Cu-based ILs reach conductivities of 10(-2) S cm(-1), which is, however, probably due to IL dec. This correlates with the optical bandgap measurements indicating the formation of large bandgap semiconductors. At elevated temperatures approaching the melting points, the conductivities reach up to 1.47x10(-1) S cm(-1) at 70 degrees C. The electrochemical stability windows of the ILs are between 2.5 and 3.0 V.
KW  - bandgap
KW  - electrochemistry
KW  - ionic liquids
KW  - metal-containing ionic
KW  - liquids
KW  - tetrahalido metallates
Y1  - 2020
U6  - https://doi.org/10.1002/chem.202003097
SN  - 0947-6539
SN  - 1521-3765
VL  - 26
IS  - 72
SP  - 17504
EP  - 17513
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - GEN
A1  - Zehbe, Kerstin
A1  - Kollosche, Matthias
A1  - Lardong, Sebastian
A1  - Kelling, Alexandra
A1  - Schilde, Uwe
A1  - Taubert, Andreas
T1  - Ionogels based on poly(methyl methacrylate) and metal-containing ionic liquids
BT  - correlation between structure and mechanical and electrical properties
N2  - Ionogels (IGs) based on poly(methyl methacrylate) (PMMA) and the metal-containing ionic liquids (ILs) bis-1-butyl-3-methlimidazolium tetrachloridocuprate(II), tetrachloride cobaltate(II), and tetrachlorido manganate(II) have been synthesized and their mechanical and electrical properties have been correlated with their microstructure. Unlike many previous examples, the current IGs show a decreasing stability in stress-strain experiments on increasing IL fractions. The conductivities of the current IGs are lower than those observed in similar examples in the literature. Both effects are caused by a two-phase structure with micrometer-sized IL-rich domains homogeneously dispersed an IL-deficient continuous PMMA phase. This study demonstrates that the IL-polymer miscibility and the morphology of the IGs are key parameters to control the (macroscopic) properties of IGs.
T3  - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 361 
KW  - microstructure
KW  - ionogels
KW  - ionic liquids
KW  - phase separation
KW  - mechanical properties
KW  - ionic conductivity
Y1  - 2017
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-400607
ER  - 
TY  - JOUR
A1  - Abouserie, Ahed
A1  - Zehbe, Kerstin
A1  - Metzner, Philipp
A1  - Kelling, Alexandra
A1  - Günter, Christina
A1  - Schilde, Uwe
A1  - Strauch, Peter
A1  - Körzdörfer, Thomas
A1  - Taubert, Andreas
T1  - Alkylpyridinium Tetrahalidometallate Ionic Liquids and Ionic Liquid Crystals: Insights into the Origin of Their Phase Behavior
JF  - European journal of inorganic chemistry : a journal of ChemPubSoc Europe
N2  - Six N-alkylpyridinium salts [CnPy](2)[MCl4] (n = 4 or 12 and M = Co, Cu, Zn) were synthesized, and their structure and thermal properties were studied. The [C4Py](2)[MCl4] compounds are monoclinic and crystallize in the space group P2(1)/n. The crystals of the longer chain analogues [C12Py](2)[MCl4] are triclinic and crystallize in the space group P (1) over bar. Above the melting temperature, all compounds are ionic liquids (ILs). The derivatives with the longer C12 chain exhibit liquid crystallinity and the shorter chain compounds only show a melting transition. Consistent with single-crystal analysis, electron paramagnetic resonance spectroscopy suggests that the [CuCl4](2-) ions in the Cu-based ILs have a distorted tetrahedral geometry.
KW  - Ionic liquids
KW  - Alkylpyridinium salts
KW  - Structure elucidation
KW  - Phase transitions
Y1  - 2017
U6  - https://doi.org/10.1002/ejic.201700826
SN  - 1434-1948
SN  - 1099-0682
SP  - 5640
EP  - 5649
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Abouserie, Ahed
A1  - Zehbe, Kerstin
A1  - Metzner, Philipp
A1  - Kelling, Alexandra
A1  - Günter, Christina
A1  - Schilde, Uwe
A1  - Strauch, Peter
A1  - Körzdörfer, Thomas
A1  - Taubert, Andreas
T1  - Alkylpyridinium Tetrahalidometallate Ionic Liquids and Ionic Liquid Crystals: Insights into the Origin of Their Phase Behavior
JF  - European journal of inorganic chemistry : a journal of ChemPubSoc Europe
N2  - Six N-alkylpyridinium salts [CnPy](2)[MCl4] (n = 4 or 12 and M = Co, Cu, Zn) were synthesized, and their structure and thermal properties were studied. The [C4Py](2)[MCl4] compounds are monoclinic and crystallize in the space group P2(1)/n. The crystals of the longer chain analogues [C12Py](2)[MCl4] are triclinic and crystallize in the space group P (1) over bar. Above the melting temperature, all compounds are ionic liquids (ILs). The derivatives with the longer C12 chain exhibit liquid crystallinity and the shorter chain compounds only show a melting transition. Consistent with single-crystal analysis, electron paramagnetic resonance spectroscopy suggests that the [CuCl4](2-) ions in the Cu-based ILs have a distorted tetrahedral geometry.
KW  - Ionic liquids
KW  - Alkylpyridinium salts
KW  - Structure elucidation
KW  - Phase transitions
Y1  - 2017
U6  - https://doi.org/10.1002/ejic.201700826
SN  - 1434-1948
SN  - 1099-0682
SP  - 5640
EP  - 5649
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - GEN
A1  - Thiel, Kerstin
A1  - Zehbe, Rolf
A1  - Roeser, Jerômé
A1  - Strauch, Peter
A1  - Enthaler, Stephan
A1  - Thomas, Arne
T1  - A polymer analogous reaction for the formation of imidazolium and NHC based porous polymer networks
N2  - A polymer analogous reaction was carried out to generate a porous polymeric network with N-heterocyclic carbenes (NHC) in the polymer backbone. Using a stepwise approach, first a polyimine network is formed by polymerization of the tetrafunctional amine tetrakis(4-aminophenyl)methane. This polyimine network is converted in the second step into polyimidazolium chloride and finally to a polyNHC network. Furthermore a porous Cu(II)-coordinated polyNHC network can be generated. Supercritical drying generates polymer networks with high permanent surface areas and porosities which can be applied for different catalytic reactions. The catalytic properties were demonstrated for example in the activation of CO2 or in the deoxygenation of sulfoxides to the corresponding sulfides.
T3  - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 243 
KW  - covalent organic framework
KW  - n-heterocyclic carbenes
KW  - carbon-dioxide
KW  - intrinsic microporosity
KW  - heterogeneous catalysis
KW  - sulfoxides
KW  - reduction
KW  - complex
KW  - system
KW  - transformation
Y1  - 2013
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-95118
SP  - 1848
EP  - 1856
ER  -