TY  - JOUR
A1  - Mai, Tobias
A1  - Boye, Susanne
A1  - Yuan, Jiayin
A1  - Völkel, Antje
A1  - Gräwert, Marlies
A1  - Günter, Christina
A1  - Lederer, Albena
A1  - Taubert, Andreas
T1  - Poly(ethylene oxide)-based block copolymers with very high molecular weights for biomimetic calcium phosphate mineralization
JF  - RSC Advances : an international journal to further the chemical sciences
N2  - The present article is among the first reports on the effects of poly(ampholyte)s and poly(betaine)s on the biomimetic formation of calcium phosphate. We have synthesized a series of di- and triblock copolymers based on a non-ionic poly(ethylene oxide) block and several charged methacrylate monomers, 2-(trimethylammonium)ethyl methacrylate chloride, 2-((3-cyanopropyl)-dimethylammonium)ethyl methacrylate chloride, 3-sulfopropyl methacrylate potassium salt, and [2-(methacryloyloxy)ethyl]dimethyl-(3-sulfopropyl)ammonium hydroxide. The resulting copolymers are either positively charged, ampholytic, or betaine block copolymers. All the polymers have very high molecular weights of over 106 g mol−1. All polymers are water-soluble and show a strong effect on the precipitation and dissolution of calcium phosphate. The strongest effects are observed with triblock copolymers based on a large poly(ethylene oxide) middle block (nominal Mn = 100 000 g mol−1). Surprisingly, the data show that there is a need for positive charges in the polymers to exert tight control over mineralization and dissolution, but that the exact position of the charge in the polymer is of minor importance for both calcium phosphate precipitation and dissolution.
Y1  - 2015
U6  - https://doi.org/10.1039/c5ra20035k
SN  - 2046-2069
IS  - 5
SP  - 103494
EP  - 103505
PB  - RSC Publishing
CY  - London
ER  - 
TY  - GEN
A1  - Mai, Tobias
A1  - Boye, Susanne
A1  - Yuan, Jiayin
A1  - Völkel, Antje
A1  - Gräwert, Marlies
A1  - Günter, Christina
A1  - Lederer, Albena
A1  - Taubert, Andreas
T1  - Poly(ethylene oxide)-based block copolymers with very high molecular weights for biomimetic calcium phosphate mineralization
N2  - The present article is among the first reports on the effects of poly(ampholyte)s and poly(betaine)s on the biomimetic formation of calcium phosphate. We have synthesized a series of di- and triblock copolymers based on a non-ionic poly(ethylene oxide) block and several charged methacrylate monomers, 2-(trimethylammonium)ethyl methacrylate chloride, 2-((3-cyanopropyl)-dimethylammonium)ethyl methacrylate chloride, 3-sulfopropyl methacrylate potassium salt, and [2-(methacryloyloxy)ethyl]dimethyl-(3-sulfopropyl)ammonium hydroxide. The resulting copolymers are either positively charged, ampholytic, or betaine block copolymers. All the polymers have very high molecular weights of over 106 g mol−1. All polymers are water-soluble and show a strong effect on the precipitation and dissolution of calcium phosphate. The strongest effects are observed with triblock copolymers based on a large poly(ethylene oxide) middle block (nominal Mn = 100 000 g mol−1). Surprisingly, the data show that there is a need for positive charges in the polymers to exert tight control over mineralization and dissolution, but that the exact position of the charge in the polymer is of minor importance for both calcium phosphate precipitation and dissolution.
T3  - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 208 
Y1  - 2015
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-85299
ER  - 
TY  - JOUR
A1  - Mai, Tobias
A1  - Boye, Susanne
A1  - Yuan, Jiayin
A1  - Voelkel, Antje
A1  - Graewert, Marlies
A1  - Günter, Christina
A1  - Lederer, Albena
A1  - Taubert, Andreas
T1  - Poly(ethylene oxide)-based block copolymers with very high molecular weights for biomimetic calcium phosphate mineralization
JF  - RSC Advances
N2  - The present article is among the first reports on the effects of poly(ampholyte)s and poly(betaine) s on the biomimetic formation of calcium phosphate. We have synthesized a series of di- and triblock copolymers based on a non-ionic poly(ethylene oxide) block and several charged methacrylate monomers, 2-(trimethylammonium) ethyl methacrylate chloride, 2-((3-cyanopropyl)-dimethylammonium)ethyl methacrylate chloride, 3-sulfopropyl methacrylate potassium salt, and [2-(methacryloyloxy)ethyl]dimethyl-(3-sulfopropyl) ammonium hydroxide. The resulting copolymers are either positively charged, ampholytic, or betaine block copolymers. All the polymers have very high molecular weights of over 10(6) g mol(-1). All polymers are water-soluble and show a strong effect on the precipitation and dissolution of calcium phosphate. The strongest effects are observed with triblock copolymers based on a large poly(ethylene oxide) middle block (nominal M-n = 100 000 g mol(-1)). Surprisingly, the data show that there is a need for positive charges in the polymers to exert tight control over mineralization and dissolution, but that the exact position of the charge in the polymer is of minor importance for both calcium phosphate precipitation and dissolution.
Y1  - 2015
U6  - https://doi.org/10.1039/c5ra20035k
SN  - 2046-2069
VL  - 5
IS  - 125
SP  - 103494
EP  - 103505
PB  - Royal Society of Chemistry
CY  - Cambridge
ER  - 
TY  - JOUR
A1  - Behrens, Karsten
A1  - Mondal, Suvendu Selchar
A1  - Nöske, Robert
A1  - Baburin, Igor A.
A1  - Leoni, Stefano
A1  - Günter, Christina
A1  - Weber, Jens
A1  - Holdt, Hans-Jürgen
T1  - Microwave-Assisted Synthesis of Defects Metal-Imidazolate-Amide-Imidate Frameworks and Improved CO2 Capture
JF  - Inorganic chemistry
N2  - In this work, we report three isostructural 3D frameworks, named IFP-11 (R = Cl), IFP-12 (R = Br), and IFP-13 (R = Et) (IFP = Imidazolate Framework Potsdam) based on a cobalt(II) center and the chelating linker 2-substituted imidazolate-4-amide-5-imidate. These chelating ligands were generated in situ by partial hydrolysis of 2-substituted 4,5-dicyanoimidazoles under microwave (MW)-assisted conditions in DMF. Structure determination of these IFPs was investigated by IR spectroscopy and a combination of powder X-ray diffraction (PXRD) with structure modeling. The structural models were initially built up from the single-crystal X-ray structure determination of IFP-5 (a cobalt center and 2-methylimidazolate-4-amide-5-imidate linker based framework) and were optimized by using density functional theory calculations. Substitution on position 2 of the linker (R = Cl, Br, and Et) in the isostructural IFP-11, -12, and -13 allowed variation of the potential pore window in 1D hexagonal channels (3.8 to 1.7 angstrom A). The potential of the materials to undergo specific interactions with CO2 was measured by the isosteric heat adsorption. Further, we resynthesized zinc based IFPs, namely IFP-1 = Me), IFP-2 (R = Cl), IFP-3 (R = Br), and IFP-4 (R = Et), and cobalt based IFP-5 under MW-assisted conditions with higher yield. The transition from a nucleation phase to the pure crystalline material of IFP-1 in MW-assisted synthesis depends on reaction time. IFP-1, -3, and -5, which are synthesized by MW-assisted conditions, showed an enhancement of N-2 and CO2, compared to the analogous conventional electrical (CE) heating method based materials due to crystal defects.
Y1  - 2015
U6  - https://doi.org/10.1021/acs.inorgchem.5b01952
SN  - 0020-1669
SN  - 1520-510X
VL  - 54
IS  - 20
SP  - 10073
EP  - 10080
PB  - American Chemical Society
CY  - Washington
ER  -