TY - JOUR A1 - Reitenbach, Julija A1 - Geiger, Christina A1 - Wang, Peixi A1 - Vagias, Apostolos N. A1 - Cubitt, Robert A1 - Schanzenbach, Dirk A1 - Laschewsky, André A1 - Papadakis, Christine M. A1 - Müller-Buschbaum, Peter T1 - Effect of magnesium salts with chaotropic anions on the swelling behavior of PNIPMAM thin films JF - Macromolecules : a publication of the American Chemical Society N2 - Poly(N-isopropylmethacrylamide) (PNIPMAM) is a stimuli responsive polymer, which in thin film geometry exhibits a volume-phase transition upon temperature increase in water vapor. The swelling behavior of PNIPMAM thin films containing magnesium salts in water vapor is investigated in view of their potential application as nanodevices. Both the extent and the kinetics of the swelling ratio as well as the water content are probed with in situ time-of-flight neutron reflectometry. Additionally, in situ Fourier-transform infrared (FTIR) spectroscopy provides information about the local solvation of the specific functional groups, while two-dimensional FTIR correlation analysis further elucidates the temporal sequence of solvation events. The addition of Mg(ClO4)2 or Mg(NO3)2 enhances the sensitivity of the polymer and therefore the responsiveness of switches and sensors based on PNIPMAM thin films. It is found that Mg(NO3)2 leads to a higher relative water uptake and therefore achieves the highest thickness gain in the swollen state. Y1 - 2023 U6 - https://doi.org/10.1021/acs.macromol.2c02282 SN - 0024-9297 SN - 1520-5835 VL - 56 IS - 2 SP - 567 EP - 577 PB - American Chemical Society CY - Washington ER - TY - JOUR A1 - Schönemann, Eric A1 - Koc, Julian A1 - Karthäuser, Jana A1 - Özcan, Onur A1 - Schanzenbach, Dirk A1 - Schardt, Lisa A1 - Rosenhahn, Axel A1 - Laschewsky, André T1 - Sulfobetaine methacrylate polymers of unconventional polyzwitterion architecture and their antifouling properties JF - Biomacromolecules : an interdisciplinary journal focused at the interface of polymer science and the biological sciences N2 - Combining high hydrophilicity with charge neutrality, polyzwitterions are intensely explored for their high biocompatibility and low-fouling properties. Recent reports indicated that in addition to charge neutrality, the zwitterion's segmental dipole orientation is an important factor for interacting with the environment. Accordingly, a series of polysulfobetaines with a novel architecture was designed, in which the cationic and anionic groups of the zwitterionic moiety are placed at equal distances from the backbone. They were investigated by in vitro biofouling assays, covering proteins of different charges and model marine organisms. All polyzwitterion coatings reduced the fouling effectively compared to model polymer surfaces of poly(butyl methacrylate), with a nearly equally good performance as the reference polybetaine poly(3-(N-(2-(methacryloyloxy)ethyl)-N,N-dimethylammonio)propanesulfonate). The specific fouling resistance depended on the detailed chemical structure of the polyzwitterions. Still, while clearly affecting the performance, the precise dipole orientation of the sulfobetaine group in the polyzwitterions seems overall to be only of secondary importance for their antifouling behavior. Y1 - 2021 U6 - https://doi.org/10.1021/acs.biomac.0c01705 SN - 1525-7797 SN - 1526-4602 VL - 22 IS - 4 SP - 1494 EP - 1508 PB - American Chemical Society CY - Washington ER - TY - JOUR A1 - Matic, Aleksandar A1 - Hess, Andreas A1 - Schanzenbach, Dirk A1 - Schlaad, Helmut T1 - Epoxidized 1,4-polymyrcene JF - Polymer chemistry N2 - 1,4-Polymyrcene was synthesized by anionic polymerization and epoxidized using meta-chloroperbenzoic acid. Samples with different degrees of epoxidation (25%, 49%, 74%, and 98%) were prepared and examined according to their chemical and thermal properties. Epoxidation was found to increase the glass transition temperature (T-g = 14 degrees C for the 98% epoxidized 1,4-polymyrcene) as well as the shelf live (>10 months). The trisubstituted epoxide groups were remarkably stable against nucleophiles under basic conditions but cross-linked or hydrolyzed in the presence of an acid. Also, highly epoxidized 1,4-polymyrcene readily cross-linked upon annealing at 260 degrees C to produce an epoxy resin. KW - comb poly(beta-myrcene)-graft-poly(l-lactide) copolymers KW - thermoplastic elastomer synthesis KW - myrcen KW - polymerization KW - epoxidation Y1 - 2020 U6 - https://doi.org/10.1039/c9py01783f SN - 1759-9954 SN - 1759-9962 VL - 11 IS - 7 SP - 1364 EP - 1368 PB - Royal Society of Chemistry CY - Cambridge ER - TY - JOUR A1 - Glatzel, Julia A1 - Noack, Sebastian A1 - Schanzenbach, Dirk A1 - Schlaad, Helmut T1 - Anionic polymerization of dienes in ‘green’ solvents JF - Polymer international N2 - Isoprene and beta-myrcene were polymerized by anionic polymerization in bulk and in the 'green' ether solvents cyclopentyl methyl ether and 2-methyltetrahydrofuran and, for comparison, in cyclohexane and tetrahydrofuran. The polydienes produced in bulk and in cyclohexane contained high amounts of 1,4 units (>90%) whereas those produced in ether solvents were rich in 1,2 and 3,4 units (36%-86%). Comparison of the microstructures and glass transition temperatures of the polydienes obtained in the various solvents suggests that conventionally used solvents can be substituted by environmentally more friendly alternatives. KW - isoprene KW - β‐myrcene KW - anionic polymerization KW - green KW - solvents KW - microstructure KW - glass transition Y1 - 2020 U6 - https://doi.org/10.1002/pi.6152 SN - 0959-8103 SN - 1097-0126 VL - 70 IS - 2 SP - 181 EP - 184 PB - Wiley CY - Hoboken ER - TY - JOUR A1 - Noack, Sebastian A1 - Schanzenbach, Dirk A1 - Koetz, Joachim A1 - Schlaad, Helmut T1 - Polylactide-based amphiphilic block copolymers BT - Crystallization-Induced Self-Assembly and Stereocomplexation JF - Macromolecular rapid communications N2 - The aqueous self-assembly behavior of a series of poly(ethylene glycol)-poly(l-/d-lactide) block copolymers and corresponding stereocomplexes is examined by differential scanning calorimetry, dynamic light scattering, and transmission electron microscopy. Block copolymers assemble into spherical micelles and worm-like aggregates at room temperature, whereby the fraction of the latter seemingly increases with decreasing lactide weight fraction or hydrophobicity. The formation of the worm-like aggregates arises from the crystallization of the polylactide by which the spherical micelles become colloidally unstable and fuse epitaxically with other micelles. The self-assembly behavior of the stereocomplex aggregates is found to be different from that of the block copolymers, resulting in rather irregular-shaped clusters of spherical micelles and pearl-necklace-like structures. KW - crystallization KW - polylactide KW - self-assembly KW - stereocomplexation Y1 - 2018 U6 - https://doi.org/10.1002/marc.201800639 SN - 1022-1336 SN - 1521-3927 VL - 40 IS - 1 PB - Wiley-VCH CY - Weinheim ER - TY - JOUR A1 - Schanzenbach, Dirk A1 - Peter, Martin G. T1 - Chromatography of chito-oligosaccarides Y1 - 1997 ER - TY - JOUR A1 - Schanzenbach, Dirk A1 - Matern, Christa-Maria A1 - Peter, Martin G. T1 - Synthesis of glycosylamines and glycopeptides Y1 - 1997 ER - TY - JOUR A1 - Schanzenbach, Dirk A1 - Peter, Martin G. T1 - NMR spectroscopy of chito-oligosaccharides Y1 - 1997 ER - TY - JOUR A1 - Schanzenbach, Dirk A1 - Matern, Christa-Maria A1 - Peter, Martin G. T1 - Cleavage of chitin by means of sulfurice acid/acetc anhydride and isolation of peracetylated chito- oligosaccharides Y1 - 1997 ER - TY - JOUR A1 - Rottmann, Antje A1 - Synstad, Bjoenar A1 - Thiele, G. A1 - Schanzenbach, Dirk A1 - Eijsink, Vincent G. H. A1 - Peter, Martin G. T1 - Approaches towards the design of new chitinase inhibitors Y1 - 1999 SN - 3-9806494-5-8 ER -