TY  - JOUR
A1  - Schroer, Guido
A1  - Toussaint, Valérie
A1  - Bachmann, Stephanie
A1  - Pöppler, Ann‐Christin
A1  - Gierlich, Christian Henning
A1  - Delidovich, Irina
T1  - Functional Phenylboronate Polymers for the Recovery of Diols, Sugar Alcohols, and Saccharides from Aqueous Solution
JF  - ChemSusChem
N2  - The ongoing transition from fossil to renewable feedstocks demands new efficient processes for an economically viable production of biomass‐derived commodities and fine chemicals. Novel energy‐ and material‐efficient product purification and separation will play a crucial role due to altered product and feed composition. The present study comprises the synthesis and tests of cross‐linked p‐vinylphenylboronate polymers for the separation of 18 diols, sugar alcohols, and saccharides, which can be obtained during biomass processing. The separation was based on molecular recognition, that is, esterification of the phenylboronate with vicinal diols. A correlation of the molecular complexation constant, the polymer swelling, and the maximum adsorption capacity was found. The adsorption curves over time were recorded. Preliminary results on competitive adsorption of binary mixtures showed a high potential for the separation of substrates with significantly different complexation constants. Desorption tests implied easier desorption of substrates that only adsorb on the outer polymer shell.
KW  - adsorption
KW  - biomass
KW  - phenylboronate
KW  - polymers
KW  - separation techniques
Y1  - 2021
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-239889
VL  - 14
IS  - 23
SP  - 5207
EP  - 5215
ER  - 
TY  - JOUR
A1  - Pöppler, Ann‐Christin
A1  - Lübtow, Michael M.
A1  - Schlauersbach, Jonas
A1  - Wiest, Johannes
A1  - Meinel, Lorenz
A1  - Luxenhofer, Robert
T1  - Strukturmodell von Polymermizellen in Abhängigkeit von der Curcumin‐Beladung mithilfe von Festkörper‐NMR‐Spektroskopie
JF  - Angewandte Chemie
N2  - Detaillierte Einblicke in die Struktur von mit Wirkstoffen beladenen Polymermizellen sind rar, aber wichtig um gezielt optimierte Transportsysteme entwickeln zu können. Wir konnten beobachten, dass eine Erhöhung der Curcumin‐Beladung von Triblockcopolymeren auf Basis von Poly(2‐oxazolinen) und Poly(2‐oxazinen) schlechtere Auflösungseigenschaften nach sich zieht. Mitthilfe von Festkörper‐NMR‐Spektroskopie und komplementären Techniken ist es möglich, ein ladungsabhängiges Strukturmodell auf molekularer Ebene zu erstellen, das eine Erklärung für die beobachteten Unterschiede liefert. Dabei belegen die Änderungen der chemischen Verschiebungen und Kreuzsignale in 2D‐NMR‐Experimenten die Beteiligung des hydrophoben Polymerblocks an der Koordination der Curcumin‐Moleküle, während bei höherer Beladung auch eine zunehmende Wechselwirkung mit dem hydrophilen Polymerblock beobachtet wird. Letztere könnte elementar für die Stabilisierung von ultrahochbeladenen Polymermizellen sowie das Design von verbesserten Wirkstofftransportsystemen sein.
KW  - Auflösungsraten
KW  - Festkörper-NMR
KW  - Mizellen
KW  - Nahordnung
KW  - Polymere
Y1  - 2019
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-212513
VL  - 131
IS  - 51
ER  - 
TY  - JOUR
A1  - Lambov, Martin
A1  - Hensiek, Nicola
A1  - Pöppler, Ann‐Christin
A1  - Lehmann, Matthias
T1  - Columnar Liquid Crystals from Star‐Shaped Conjugated Mesogens as Nano‐Reservoirs for Small Acceptors
JF  - ChemPlusChem
N2  - Shape‐persistent conjugated mesogens with oligothiophene arms of different lengths have been synthesized. Such mesogens possess free intrinsic space between their conjugated arms. They form columnar liquid‐crystalline phases, in which the void is filled by dense helical packing in the neat phase similar to an oligo(phenylene vinylene) derivative of equal size. The void can also be compensated by the inclusion of the small acceptor molecule 2,4,7‐trinitrofluorenone. In solution, the acceptor interacts with the core as the largest π‐surface, while in the solid material, it is incorporated between the arms and sandwiched by the star‐shaped neighbours along the columnar assemblies. The TNF acceptors are not nanosegregated from the star‐shaped donors, thus the liquid crystal structure converts to a nano‐reservoir for TNF (endo‐receptor). These host–guest arrangements are confirmed by comprehensive X‐ray scattering experiments and solid‐state NMR spectroscopy. This results in ordered columnar hexagonal phases at high temperatures, which change to helical columnar mesophases or to columnar soft crystals at room temperature.
KW  - donor-acceptor interactions
KW  - host-guest systems
KW  - intrinsic free space
KW  - liquid crystals
KW  - mesogens
Y1  - 2020
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-218014
VL  - 85
IS  - 10
SP  - 2219
EP  - 2229
ER  -