@article{SchroerToussaintBachmannetal.2021, author = {Schroer, Guido and Toussaint, Val{\´e}rie and Bachmann, Stephanie and P{\"o}ppler, Ann-Christin and Gierlich, Christian Henning and Delidovich, Irina}, title = {Functional Phenylboronate Polymers for the Recovery of Diols, Sugar Alcohols, and Saccharides from Aqueous Solution}, series = {ChemSusChem}, volume = {14}, journal = {ChemSusChem}, number = {23}, doi = {10.1002/cssc.202002887}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-239889}, pages = {5207 -- 5215}, year = {2021}, abstract = {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.}, language = {en} } @article{PoepplerLuebtowSchlauersbachetal.2019, author = {P{\"o}ppler, Ann-Christin and L{\"u}btow, Michael M. and Schlauersbach, Jonas and Wiest, Johannes and Meinel, Lorenz and Luxenhofer, Robert}, title = {Strukturmodell von Polymermizellen in Abh{\"a}ngigkeit von der Curcumin-Beladung mithilfe von Festk{\"o}rper-NMR-Spektroskopie}, series = {Angewandte Chemie}, volume = {131}, journal = {Angewandte Chemie}, number = {51}, doi = {10.1002/ange.201908914}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-212513}, pages = {18712-18718}, year = {2019}, abstract = {Detaillierte Einblicke in die Struktur von mit Wirkstoffen beladenen Polymermizellen sind rar, aber wichtig um gezielt optimierte Transportsysteme entwickeln zu k{\"o}nnen. Wir konnten beobachten, dass eine Erh{\"o}hung der Curcumin-Beladung von Triblockcopolymeren auf Basis von Poly(2-oxazolinen) und Poly(2-oxazinen) schlechtere Aufl{\"o}sungseigenschaften nach sich zieht. Mitthilfe von Festk{\"o}rper-NMR-Spektroskopie und komplement{\"a}ren Techniken ist es m{\"o}glich, ein ladungsabh{\"a}ngiges Strukturmodell auf molekularer Ebene zu erstellen, das eine Erkl{\"a}rung f{\"u}r die beobachteten Unterschiede liefert. Dabei belegen die {\"A}nderungen der chemischen Verschiebungen und Kreuzsignale in 2D-NMR-Experimenten die Beteiligung des hydrophoben Polymerblocks an der Koordination der Curcumin-Molek{\"u}le, w{\"a}hrend bei h{\"o}herer Beladung auch eine zunehmende Wechselwirkung mit dem hydrophilen Polymerblock beobachtet wird. Letztere k{\"o}nnte elementar f{\"u}r die Stabilisierung von ultrahochbeladenen Polymermizellen sowie das Design von verbesserten Wirkstofftransportsystemen sein.}, language = {de} } @article{LambovHensiekPoeppleretal.2020, author = {Lambov, Martin and Hensiek, Nicola and P{\"o}ppler, Ann-Christin and Lehmann, Matthias}, title = {Columnar Liquid Crystals from Star-Shaped Conjugated Mesogens as Nano-Reservoirs for Small Acceptors}, series = {ChemPlusChem}, volume = {85}, journal = {ChemPlusChem}, number = {10}, doi = {10.1002/cplu.202000341}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-218014}, pages = {2219 -- 2229}, year = {2020}, abstract = {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.}, language = {en} }