@article{InalKoelschSelrieetal.2013,
  author    = {Inal, Sahika and K{\"o}lsch, Jonas D. and Selrie, Frank and Schenk, J{\"o}rg A. and Wischerhoff, Erik and Laschewsky, Andr{\´e} and Neher, Dieter},
  title     = {A water soluble fluorescent polymer as a dual colour sensor for temperature and a specific protein},
  doi       = {10.1039/c3tb21245a},
  year      = {2013},
  abstract  = {We present two thermoresponsive water soluble copolymers prepared via free radical statistical copolymerization of N-isopropylacrylamide (NIPAm) and of oligo(ethylene glycol) methacrylates (OEGMAs), respectively, with a solvatochromic 7-(diethylamino)-3-carboxy-coumarin (DEAC)-functionalized monomer. In aqueous solutions, the NIPAm-based copolymer exhibits characteristic changes in its fluorescence profile in response to a change in solution temperature as well as to the presence of a specific protein, namely an anti-DEAC antibody. This polymer emits only weakly at low temperatures, but exhibits a marked fluorescence enhancement accompanied by a change in its emission colour when heated above its cloud point. Such drastic changes in the fluorescence and absorbance spectra are observed also upon injection of the anti-DEAC antibody, attributed to the specific binding of the antibody to DEAC moieties. Importantly, protein binding occurs exclusively when the polymer is in the well hydrated state below the cloud point, enabling a temperature control on the molecular recognition event. On the other hand, heating of the polymer-antibody complexes releases a fraction of the bound antibody. In the presence of the DEAC-functionalized monomer in this mixture, the released antibody competitively binds to the monomer and the antibody-free chains of the polymer undergo a more effective collapse and inter-aggregation. In contrast, the emission properties of the OEGMA-based analogous copolymer are rather insensitive to the thermally induced phase transition or to antibody binding. These opposite behaviours underline the need for a carefully tailored molecular design of responsive polymers aimed at specific applications, such as biosensing.},
  language  = {en}
}
@misc{InalKoelschSellrieetal.2013,
  author    = {Inal, Sahika and K{\"o}lsch, Jonas D. and Sellrie, Frank and Schenk, J{\"o}rg A. and Wischerhoff, Erik and Laschewsky, Andr{\´e} and Neher, Dieter},
  title     = {A water soluble fluorescent polymer as a dual colour sensor for temperature and a specific protein},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-95336},
  pages     = {6373 -- 6381},
  year      = {2013},
  abstract  = {We present two thermoresponsive water soluble copolymers prepared via free radical statistical copolymerization of N-isopropylacrylamide (NIPAm) and of oligo(ethylene glycol) methacrylates (OEGMAs), respectively, with a solvatochromic 7-(diethylamino)-3-carboxy-coumarin (DEAC)- functionalized monomer. In aqueous solutions, the NIPAm-based copolymer exhibits characteristic changes in its fluorescence profile in response to a change in solution temperature as well as to the presence of a specific protein, namely an anti-DEAC antibody. This polymer emits only weakly at low temperatures, but exhibits a marked fluorescence enhancement accompanied by a change in its emission colour when heated above its cloud point. Such drastic changes in the fluorescence and absorbance spectra are observed also upon injection of the anti-DEAC antibody, attributed to the specific binding of the antibody to DEAC moieties. Importantly, protein binding occurs exclusively when the polymer is in the well hydrated state below the cloud point, enabling a temperature control on the molecular recognition event. On the other hand, heating of the polymer-antibody complexes releases a fraction of the bound antibody. In the presence of the DEAC-functionalized monomer in this mixture, the released antibody competitively binds to the monomer and the antibody-free chains of the polymer undergo a more effective collapse and inter-aggregation. In contrast, the emission properties of the OEGMA-based analogous copolymer are rather insensitive to the thermally induced phase transition or to antibody binding. These opposite behaviours underline the need for a carefully tailored molecular design of responsive polymers aimed at specific applications, such as biosensing.},
  language  = {en}
}
@article{WattebledLaschewskyMoussaetal.2006,
  author    = {Wattebled, Laurent and Laschewsky, Andr{\´e} and Moussa, Alain and Habib-Jiwan, Jean-Louis},
  title     = {Aggregation numbers of cationic oligomeric surfactants : A time-resolved fluorescence quenching study},
  doi       = {10.1021/La052414h},
  year      = {2006},
  abstract  = {The micelle aggregation numbers (N-agg) of several series of cationic oligomeric surfactants were determined by time-resolved fluorescence quenching (TRFQ) experiments, using advantageously 9,10-dimethylanthracene as fluorophore. The study comprises six dimeric ("gemini"), three trimeric, and two tetrameric surfactants, which are quaternary ammonium chlorides, with medium length spacer groups (C-3-C-6) separating the individual surfactant fragments. Two standard cationic surfactants served as references. The number of hydrophobic chains making up a micellar core is relatively low for the oligomeric surfactants, the spacer length playing an important role. For the dimers, the number decreases from 32 to 21 with increasing spacer length. These numbers decrease further with increasing degree of oligomerization down to values of about 15. As for many conventional ionic surfactants, the micelles of all oligomers studied grow only slightly with the concentration, and they remain in the regime of small micelles up to concentrations of at least 3 wt \%.},
  language  = {en}
}
@article{LaschewskyMallwitzBaussardetal.2004,
  author    = {Laschewsky, Andr{\´e} and Mallwitz, Frank and Baussard, Jean-Francois and Cochin, Didier and Fischer, Peter and Habib-Jiwan, Jean-Louis and Wischerhoff, Erik},
  title     = {Aggregation phenomena in polyelectrolyte multilayers made from polyelectrolytes bearing bulky functional, hydrophobic fragments},
  year      = {2004},
  abstract  = {The functionalization of polyelectrolyte multilayers often implies the use of bulky functional fragments, attached to a standard polyelectrolyte matrix. Despite of the high density of non-charged, often hydrophobic substituents, regular film growth by sequential adsorption proceeds easily when an appropriate polyelectrolyte counter ion is chosen. However, the functional fragments may cluster or aggregate. This complication is particularly evident when using chromophores and fluorophores as bulky pendant groups. Attention has to be paid to this phenomenon for the design of functional polyelectrolyte films, as aggregation may modify crucially the properties. The use of charged spacer groups does not necessarily suppress the aggregation of functional side groups. Still, clustering and aggregation depend on the detailed system employed, and are not obligatory. In the case of cationic poly(acrylamide)s labeled with naphthalene and pyrene fluorophores, for instance, the polymers form intramolecular hydrophobic associates in solution, as indicated by strong excimer formation. But the polymers can undergo a conformational rearrangement upon adsorption so that they are decoiled in the adsorbed films. Analogous observations are made for polyanions bearing mesogenic biphenyls fragments. In contrast, polycations functionalized with the dye coumarin 343 show little aggregation in solution, but a marked aggregation in the ESA films},
  language  = {en}
}
@article{VishnevetskayaHildebrandNizardoetal.2019,
  author    = {Vishnevetskaya, Natalya S. and Hildebrand, Viet and Nizardo, Noverra Mardhatillah and Ko, Chia-Hsin and Di, Zhenyu and Radulescu, Aurel and Barnsley, Lester C. and M{\"u}ller-Buschbaum, Peter and Laschewsky, Andr{\´e} and Papadakis, Christine M.},
  title     = {All-in-One "Schizophrenic" self-assembly of orthogonally tuned thermoresponsive diblock copolymers},
  series = {Langmuir},
  volume    = {35},
  journal   = {Langmuir},
  number    = {19},
  publisher = {American Chemical Society},
  address   = {Washington},
  issn      = {0743-7463},
  doi       = {10.1021/acs.langmuir.9b00241},
  pages     = {6441 -- 6452},
  year      = {2019},
  abstract  = {Smart, fully orthogonal switching was realized in a highly biocompatible diblock copolymer system with variable trigger-induced aqueous self-assembly. The polymers are composed of nonionic and zwitterionic blocks featuring lower and upper critical solution temperatures (LCSTs and UCSTs). In the system investigated, diblock copolymers from poly(N-isopropyl methacrylamide) (PNIPMAM) and a poly(sulfobetaine methacrylamide), systematic variation of the molar mass of the latter block allowed for shifting the UCST of the latter above the LCST of the PNIPMAM block in a salt-free condition. Thus, successive thermal switching results in "schizophrenic" micellization, in which the roles of the hydrophobic core block and the hydrophilic shell block are interchanged depending on the temperature. Furthermore, by virtue of the strong electrolyte-sensitivity of the zwitterionic polysulfobetaine block, we succeeded to shift its UCST below the LCST of the PNIPMAM block by adding small amounts of an electrolyte, thus inverting the pathway of switching. This superimposed orthogonal switching by electrolyte addition enabled us to control the switching scenarios between the two types of micelles (i) via an insoluble state, if the LCST-type cloud point is below the UCST-type cloud point, which is the case at low salt concentrations or (ii) via a molecularly dissolved state, if the LCST-type cloud point is above the UCST-type cloud point, which is the case at high salt concentrations. Systematic variation of the block lengths allowed for verifying the anticipated behavior and identifying the molecular architecture needed. The versatile and tunable self-assembly offers manifold opportunities, for example, for smart emulsifiers or for sophisticated carrier systems.},
  language  = {en}
}
@article{ZehmLaschewskyGradzielskietal.2010,
  author    = {Zehm, Daniel and Laschewsky, Andr{\´e} and Gradzielski, Michael and Pr{\´e}vost, Sylvain and Liang, Hua and Rabe, J{\"u}rgen P. and Schweins, Ralf and Gummel, J{\´e}r{\´e}mie},
  title     = {Amphiphilic dual brush block copolymers as "giant surfactants" and their aqueous self-assembly},
  issn      = {0743-7463},
  doi       = {10.1021/La903087p},
  year      = {2010},
  abstract  = {Amphiphilic dual brush diblock as well as symmetrical triblock polymers were synthesized by the overlay of the reversible addition-fragmentation chain transfer and the nitroxide mediated polymerization (NMP) techniques. While poly(ethylene glycol) brushes served as hydrophilic block, the hydrophobic block was made of polystyrene brushes. The resulting "giant surfactants" correspond structurally to the established amphiphilic diblock and triblock copolymer known as macrosurfactants. The aggregation behavior of the novel "giant surfactants" in aqueous solution was studied by dynamic light scattering, small-angle neutron scattering (SANS), and small-angle X-ray scattering (SAXS) over a large range in reciprocal space. Further, the self-assembled aggregates Were investigated by scanning force microscopy (SFM) after deposition on differently functionalized ultraflat solid substrates. Despite the high fraction of hydrophobic segments, the polymers form stable mesoscopic, spherical aggregates with hydrodynamic diameters in the range of 150-350 nm. Though prepared from well-defined individual polymers, the aggregates show several similarities to hard core latexes. They are stable enough to he deposited without much changes onto surfaces, where they cluster and show Spontaneous sorting according to their size within the clusters, with the larger aggregates being in the center.},
  language  = {en}
}
@misc{BubeckLaschewskyLupoetal.1991,
  author    = {Bubeck, Christoph and Laschewsky, Andr{\´e} and Lupo, Donald and Neher, Dieter and Ottenbreit, Petra and Paulus, Wolfgang and Prass, Werner and Ringsdorf, Helmut and Wegner, Gerhard},
  title     = {Amphiphilic dyes for nonlinear optics: Dependence of second harmonic generation on functional group substitution},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-17201},
  year      = {1991},
  language  = {en}
}
@article{WeissWienkBoelensetal.2014,
  author    = {Weiss, Jan and Wienk, Hans and Boelens, Rolf and Laschewsky, Andr{\´e}},
  title     = {Block copolymer micelles with an intermediate star-/flower-like structure studied by H-1 NMR relaxometry},
  series = {Macromolecular chemistry and physics},
  volume    = {215},
  journal   = {Macromolecular chemistry and physics},
  number    = {9},
  publisher = {Wiley-VCH},
  address   = {Weinheim},
  issn      = {1022-1352},
  doi       = {10.1002/macp.201300753},
  pages     = {915 -- 919},
  year      = {2014},
  abstract  = {H-1 NMR relaxation is used to study the self-assembly of a double thermoresponsive diblock copolymer in dilute aqueous solution. Above the first transition temperature, at which aggregation into micellar structures is observed, the trimethylsilyl (TMS)-labeled end group attached to the shell-forming block shows a biphasic T-2 relaxation. The slow contribution reflects the TMS groups located at the periphery of the hydrophilic shell, in agreement with a star-like micelle. The fast T-2 contribution corresponds to the TMS groups, which fold back toward the hydrophobic core, reflecting a flower-like micelle. These results confirm the formation of block copolymer micelles of an intermediate nature (i.e., of partial flower-like and star-like character), in which a part of the TMS end groups folds back to the core due to hydrophobic interactions.},
  language  = {en}
}
@article{RullensLaschewskyDevillers2006,
  author    = {Rullens, F and Laschewsky, Andr{\´e} and Devillers, M},
  title     = {Bulk and thin films of bismuth vanadates prepared from hybrid materials made from an organic polymer and inorganic salts},
  doi       = {10.1021/Cm051516q},
  year      = {2006},
  abstract  = {A new precursor route for the preparation of bulk oxides and thin films of bismuth vanadates is proposed. The method involves the thermal treatment under air and mild conditions of hybrid organic-inorganic precursors, made from a zwitterionic salt-free polymer matrix and selected inorganic species. Monoclinic BiVO4 was obtained in the form of bulk oxide by calcination of the powdered homogeneous hybrid materials at 600 degrees C, from precursors containing Bi and V in stoichiometric amounts. In the same way, thermodiffractometry studies performed on a hybrid material exhibiting a Bi/ V molar ratio of 2 revealed that the ionic conductor gamma-Bi4V2O11 phase can be stabilized under very soft thermal conditions (300 degrees C). Additionally, thin films of yellow monoclinic BiVO4 were for the first time fabricated, by thermal treatment of the same hybrid polymeric precursors deposited on quartz substrates by spin coating, using a layer- by-layer technique. The presence of the target phase at the surface of the plates was confirmed by X-ray diffraction as well as UV-vis measurements},
  language  = {en}
}
@article{SzczubialkaMoczekGoliszeketal.2005,
  author    = {Szczubialka, K. and Moczek, Lukasz and Goliszek, A. and Nowakowska, M. and Kotzev, Anton and Laschewsky, Andr{\´e}},
  title     = {Characterization of hydrocarbon and fluorocarbon microdomains formed in aqueous solution of associative polymers : a molecular probe technique},
  issn      = {0022-1139},
  year      = {2005},
  abstract  = {Fluorocarbon associative polymers of the polysoap type were studied using two fluorescent probes, 1- octanoylpyrene (OcPyH) and 1-perfluorooctanoylpyrene (OcPyF). In aqueous solution the polymers formed hydrophobic domains composed of hydrocarbon, fluorocarbon or both types of polymeric side chains, which could solubilize the probes. This resulted in the appearance of new fluorescence emission bands and changes in the fluorescence polarization of the probes. The differences in the solubilization properties of the polymers are discussed. (c) 2005 Elsevier B.V. All rights reserved},
  language  = {en}
}
@article{FandrichFalkenhagenWeidneretal.2010,
  author    = {Fandrich, Nick and Falkenhagen, Jana and Weidner, Steffen M. and Pfeifer, Dietmar and Staal, Bastiaan and Thuenemann, Andreas F. and Laschewsky, Andr{\´e}},
  title     = {Characterization of new amphiphilic block copolymers of N-vinyl pyrrolidone and vinyl acetate, 1-analysis of copolymer composition, end groups, molar masses and molar mass distributions},
  issn      = {1022-1352},
  doi       = {10.1002/macp.200900466},
  year      = {2010},
  abstract  = {New amphiphilic block copolymers consisting of N-vinyl pyrrolidone and vinyl acetate were synthesized via controlled radical polymerization using a reversible addition/fragmentation chain transfer (RAFT)/macromolecular design via the interchange of xanthates (MADIX) system. The synthesis was carried out in 1,4-dioxane as process solvent. In order to get conclusions on the mechanism of the polymerization the molecular structure of formed copolymers was analysed by means of different analytical techniques. C-13 NMR spectroscopy was used for the determination of the monomer ratios. End groups were analysed by means of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. This technique was also used to determine possible fragmentations of the RAFT end groups. By means of a combination of size exclusion chromatography, C-13 NMR and static light scattering molar mass distributions and absolute molar masses could be analysed. The results clearly show a non-ideal RAFT mechanism.},
  language  = {en}
}
@article{FandrichFalkenhagenWeidneretal.2010,
  author    = {Fandrich, Nick and Falkenhagen, Jana and Weidner, Steffen M. and Staal, Bastiaan and Thuenemann, Andreas F. and Laschewsky, Andr{\´e}},
  title     = {Characterization of new amphiphilic block copolymers of N-vinylpyrrolidone and vinyl acetate, 2-chromatographic separation and analysis by MALDI-TOF and FT-IR coupling},
  issn      = {1022-1352},
  doi       = {10.1002/macp.201000044},
  year      = {2010},
  abstract  = {PVP-block-PVAc block copolymers were synthesized by controlled radical polymerization applying a RAFT/MADIX system and were investigated by HPLC and by coupling of chromatography to FT-IR spectroscopy and MALDI-TOF MS. Chromatographic methods (LACCC and gradient techniques) were developed that allowed a separation of block copolymers according to their repeating units. The results of the spectroscopic and spectrometric analysis clearly showed transfer between radicals and process solvent. With the use of hyphenated techniques differences between main and side products were detected. In agreement with previously published results, obtained by NMR, SEC, static light scattering and MALDI- TOF MS, our data proved a non-ideal RAFT polymerization.},
  language  = {en}
}
@article{LaschewskyGarnierKirstenetal.2006,
  author    = {Laschewsky, Andr{\´e} and Garnier, Sebastien and Kirsten, Juliane and Mertoglu, Murat and Skrabania, Katja and Lutz, Jean-Francois},
  title     = {Comb-like polymeric surfactants by combining block and graft copolymer architectures},
  issn      = {0065-7727},
  year      = {2006},
  language  = {en}
}
@article{vonBerlepschBoettcherSkrabaniaetal.2009,
  author    = {von Berlepsch, Hans and Boettcher, Christoph and Skrabania, Katja and Laschewsky, Andr{\´e}},
  title     = {Complex domain architecture of multicompartment micelles from a linear ABC triblock copolymer revealed by cryogenic electron tomography},
  issn      = {1359-7345},
  doi       = {10.1039/B903658j},
  year      = {2009},
  abstract  = {Cryo-electron tomography of raspberry-like multicompartment micelles formed by a linear ABC triblock copolymer in water revealed that the fluorocarbon domains may be dispersed all over the hydrocarbon core.},
  language  = {en}
}
@article{KyriakosPhilippAdelsbergeretal.2014,
  author    = {Kyriakos, Konstantinos and Philipp, Martine and Adelsberger, Joseph and Jaksch, Sebastian and Berezkin, Anatoly V. and Lugo, Dersy M. and Richtering, Walter and Grillo, Isabelle and Miasnikova, Anna and Laschewsky, Andr{\´e} and M{\"u}ller-Buschbaum, Peter and Papadakis, Christine M.},
  title     = {Cononsolvency of water/methanol mixtures for PNIPAM and PS-b-PNIPAM: pathway of aggregate formation investigated using time-resolved SANS},
  series = {Macromolecules : a publication of the American Chemical Society},
  volume    = {47},
  journal   = {Macromolecules : a publication of the American Chemical Society},
  number    = {19},
  publisher = {American Chemical Society},
  address   = {Washington},
  issn      = {0024-9297},
  doi       = {10.1021/ma501434e},
  pages     = {6867 -- 6879},
  year      = {2014},
  abstract  = {We investigate the cononsolvency effect of poly(N-isopropylacrylamide) (PNIPAM) in mixtures of water and methanol. Two systems are studied: micellar solutions of polystyrene-b-poly(N-isopropylacrylamide) (PS-b-PNIPAM) diblock copolymers and, as a reference, solutions of PNIPAM homopolymers, both at a concentration of 20 mg/mL in DO. Using a stopped-flow instrument, fully deuterated methanol was rapidly added to these solutions at volume fractions between 10 and 20\%. Time-resolved turbidimetry revealed aggregate formation within 10-100 s. The structural changes on mesoscopic length scales were followed by time-resolved small-angle neutron scattering (TR-SANS) with a time resolution of 0.1 s. In both systems, the pathway of the aggregation depends on the content of deuterated methanol; however, it is fundamentally different for homopolymer and diblock copolymer solutions: In the former, very large aggregates (>150 nm) are formed within the dead time of the setup, gradient appears at their surface in the late stages. In contrast, the growth of the aggregates in the latter system features different regimes, and the final aggregate size is 50 nm, thus much smaller than for the homopolymer. For the diblock copolymer, the time dependence of the aggregate radius can be described by two models: In the initial stage, the diffusion-limited coalescence model describes the data well; however, the resulting coalescence time is unreasonably high. In the late stage, a logarithmic coalescence model based on an energy barrier which is proportional to the aggregate radius is successfully applied. and a concentration},
  language  = {en}
}
@article{MiasnikovaBenitezMontoyaLaschewsky2013,
  author    = {Miasnikova, Anna and Benitez-Montoya, Carlos Adrian and Laschewsky, Andr{\´e}},
  title     = {Counterintuitive photomodulation of the thermal phase transition of poly(methoxy diethylene glycol acrylate) in aqueous solution by trans-cis isomerization of Copolymerized Azobenzenes},
  series = {Macromolecular chemistry and physics},
  volume    = {214},
  journal   = {Macromolecular chemistry and physics},
  number    = {13},
  publisher = {Wiley-VCH},
  address   = {Weinheim},
  issn      = {1022-1352},
  doi       = {10.1002/macp.201300203},
  pages     = {1504 -- 1514},
  year      = {2013},
  abstract  = {The non-ionic monomer (methoxy diethylene glycol) acrylate is copolymerized with its azodye-functionalized acrylate analogue using reversible addition-fragmentation chain transfer (RAFT) polymerization. Copolymerization is increasingly difficult with increasing amounts of the azo-dye-bearing monomer. The resulting water-soluble polymers are thermosensitive, exhibiting lower critical solution temperature (LCST) behavior, which can be modulated by the photoinduced trans-cis isomerization of the dye. While already small contents of the hydrophobic azobenzene group reduce the phase-transition temperatures of the copolymers strongly, photoisomerization of the apolar trans-state to the more-polar cis-state has only a small effect, and decreases rather than increases the cloud points.},
  language  = {en}
}
@article{LaschewskyKirstenSkrabaniaetal.2006,
  author    = {Laschewsky, Andr{\´e} and Kirsten, Juliane and Skrabania, Katja and Storsberg, Joachim},
  title     = {Designing functional macrosurfactants via triblock tercopolymers},
  issn      = {0065-7727},
  year      = {2006},
  language  = {en}
}
@article{MallwitzLaschewsky2005,
  author    = {Mallwitz, Frank and Laschewsky, Andr{\´e}},
  title     = {Direct access to stable, freestanding polymer membranes by layer-by-layer assembly of polyelectrolytes},
  issn      = {0935-9648},
  year      = {2005},
  abstract  = {A novel method to prepare ultrathin, freestanding polyelectrolyte films in pores, without the need of sacrificial precursor coatings, has been developed (see Figure). The freestanding films are stable under ambient conditions and suited for additional electrostatic self-assembly or surface modification. They can be specifically decomposed, whereas after thermal crosslinking, resistant films are obtained},
  language  = {en}
}
@article{VirtanenArotcarenaHeiseetal.2002,
  author    = {Virtanen, Janne and Arotcarena, Michel and Heise, Bettina and Ishaya, Sultana and Laschewsky, Andr{\´e} and Tenhu, Heikki},
  title     = {Dissolution and aggregation of a poly (NIPA-block-sulfobetaine) copolymer in pure and saline aqueous solutions},
  year      = {2002},
  abstract  = {Thermal properties of block copolymer, poly(N-isopropyl acrylamide)-block-poly(3-[N-(3-methacrylamido-propyl)- N,N-dimethyl]-ammonio propane sulfonate), PNIPA-b-PSPP have been studied in pure and saline (NaCl) aqueous solutions by dynamic laser light scattering (DLS). The copolymer [Mw(PNIPA) 10800 g/mol and Mw(PSPP) 9700 g/mol] exhibits both an upper (UCST 9 oC) and lower (LCST 32 oC) critical solution temperatures in pure water. The addition of NaCl enhances the solubility of the zwitterionic polymer, PSPP, leading to the disappearance of the UCST. On the other hand, the solubility of PNIPA in water decreases as NaCl is added. At 20 oC the copolymer shows a bimodal size distribution through the NaCl concentration range of 0-0.93 M above a certain limiting polymer concentration. The slow and fast components of the diffusion coefficients of the polymer have been calculated. A gradual addition of salt turns the mutual interactions from zwitterionic attractions between PSPP blocks to hydrophobic attractions between PNIPA blocks. The formation of the aggregates and the aggregate sizes at T < UCST and T > LCST are influenced by polymer and salt concentrations. Below UCST the aggregates in saline polymer solutions are larger than those in pure polymer solutions. Above LCST the aggregate size is determined by the salt concentration.},
  language  = {en}
}
@article{KocSchardtNolteetal.2020,
  author    = {Koc, Julian and Schardt, Lisa and Nolte, Kim and Beyer, Cindy and Eckhard, Till and Schwiderowski, Philipp and Clarke, Jessica L. and Finlay, John A. and Clare, Anthony S. and Muhler, Martin and Laschewsky, Andr{\´e} and Rosenhahn, Axel},
  title     = {Effect of dipole orientation in mixed, charge-equilibrated self-assembled monolayers on protein adsorption and marine biofouling},
  series = {ACS applied materials \& interfaces},
  volume    = {12},
  journal   = {ACS applied materials \& interfaces},
  number    = {45},
  publisher = {American Chemical Society},
  address   = {Washington},
  issn      = {1944-8244},
  doi       = {10.1021/acsami.0c11580},
  pages     = {50953 -- 50961},
  year      = {2020},
  abstract  = {While zwitterionic interfaces are known for their excellent low-fouling properties, the underlying molecular principles are still under debate. In particular, the role of the zwitterion orientation at the interface has been discussed recently. For elucidation of the effect of this parameter, self-assembled monolayers (SAMs) on gold were prepared from stoichiometric mixtures of oppositely charged alkyl thiols bearing either a quaternary ammonium or a carboxylate moiety. The alkyl chain length of the cationic component (11-mercaptoundecyl)-N,N,N-trimethylammonium, which controls the distance of the positively charged end group from the substrate's surface, was kept constant. In contrast, the anionic component and, correspondingly, the distance of the negatively charged carboxylate groups from the surface was varied by changing the alkyl chain length in the thiol molecules from 7 (8-mercaptooctanoic acid) to 11 (12-mercaptododecanoic acid) to 15 (16-mercaptohexadecanoic acid). In this way, the charge neutrality of the coating was maintained, but the charged groups exposed at the interface to water were varied, and thus, the orientation of the dipoles in the SAMs was altered. In model biofouling studies, protein adsorption, diatom accumulation, and the settlement of zoospores were all affected by the altered charge distribution. This demonstrates the importance of the dipole orientation in mixed-charged SAMs for their inertness to nonspecific protein adsorption and the accumulation of marine organisms. Overall, biofouling was lowest when both the anionic and the cationic groups were placed at the same distance from the substrate's surface.},
  language  = {en}
}
@article{DodooBalzerHugeletal.2013,
  author    = {Dodoo, Samuel and Balzer, Bizan N. and Hugel, Thorsten and Laschewsky, Andr{\´e} and von Klitzing, Regine},
  title     = {Effect of ionic strength and layer number on swelling of polyelectrolyte multilayers in water vapour},
  series = {Soft materials},
  volume    = {11},
  journal   = {Soft materials},
  number    = {2},
  publisher = {Taylor \& Francis Group},
  address   = {Philadelphia},
  issn      = {1539-445X},
  doi       = {10.1080/1539445X.2011.607203},
  pages     = {157 -- 164},
  year      = {2013},
  abstract  = {The swelling behavior of polyelectrolyte multilayers (PEMs) of poly(sodium-4 styrene sulfonate) (PSS) and poly(diallyl dimethyl ammonium chloride) (PDADMAC) prepared from aqueous solution of 0.1 M and 0.5 M NaCl are investigated by ellipsometry and Atomic Force Microscopy (AFM). From 1 double-layer up to 4 double-layers of 0.1 M NaCl, the amount of swelling water in the PEMs decreases with increasing number of adsorbed double layers due to an increase in polyelectrolyte density as a result of the attraction between the positively charged outermost PDADMAC layer and the Si substrate. From 6 double layers to 30 double layers, the attraction is reduced due to a much larger distance between substrate and outermost layer leading to a much lower polyelectrolyte density and higher swelling water. In PEMs prepared from aqueous solution of 0.5 M NaCl, the amount of water constantly increases which is related to a monotonically decreasing polyelectrolyte density with increasing number of polyelectrolyte layers. Studies of the surface topology also indicate a transition from a more substrate affected interphase behavior to a continuum properties of the polyelectrolyte multilayers. The threshold for the transition from interphase to continuum behavior depends on the preparation conditions of the PEM.},
  language  = {en}
}
@article{DodooSteitzLaschewskyetal.2011,
  author    = {Dodoo, S. and Steitz, R. and Laschewsky, Andr{\´e} and von Klitzing, Regine},
  title     = {Effect of ionic strength and type of ions on the structure of water swollen polyelectrolyte multilayers},
  series = {Physical chemistry, chemical physics : a journal of European Chemical Societies},
  volume    = {13},
  journal   = {Physical chemistry, chemical physics : a journal of European Chemical Societies},
  number    = {21},
  publisher = {Royal Society of Chemistry},
  address   = {Cambridge},
  issn      = {1463-9076},
  doi       = {10.1039/c0cp01357a},
  pages     = {10318 -- 10325},
  year      = {2011},
  abstract  = {This study addresses the effect of ionic strength and type of ions on the structure and water content of polyelectrolyte multilayers. Polyelectrolyte multilayers of poly(sodium-4-styrene sulfonate) (PSS) and poly(diallyl dimethyl ammonium chloride) (PDADMAC) prepared at different NaF, NaCl and NaBr concentrations have been investigated by neutron reflectometry against vacuum, H2O and D2O. Both thickness and water content of the multilayers increase with increasing ionic strength and increasing ion size. Two types of water were identified, "void water" which fills the voids of the multilayers and does not contribute to swelling but to a change in scattering length density and "swelling water" which directly contributes to swelling of the multilayers. The amount of void water decreases with increasing salt concentration and anion radius while the amount of swelling water increases with salt concentration and anion radius. This is interpreted as a denser structure in the dry state and larger ability to swell in water (sponge) for multilayers prepared from high ionic strengths and/or salt solution of large anions. No exchange of hydration water or replacement of H by D was detected even after eight hours incubation time in water of opposing isotopic composition.},
  language  = {en}
}
@article{ReitenbachGeigerWangetal.2023,
  author    = {Reitenbach, Julija and Geiger, Christina and Wang, Peixi and Vagias, Apostolos N. and Cubitt, Robert and Schanzenbach, Dirk and Laschewsky, Andr{\´e} and Papadakis, Christine M. and M{\"u}ller-Buschbaum, Peter},
  title     = {Effect of magnesium salts with chaotropic anions on the swelling behavior of PNIPMAM thin films},
  series = {Macromolecules : a publication of the American Chemical Society},
  volume    = {56},
  journal   = {Macromolecules : a publication of the American Chemical Society},
  number    = {2},
  publisher = {American Chemical Society},
  address   = {Washington},
  issn      = {0024-9297},
  doi       = {10.1021/acs.macromol.2c02282},
  pages     = {567 -- 577},
  year      = {2023},
  abstract  = {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.},
  language  = {en}
}
@misc{HildebrandLaschewskyPaechetal.2016,
  author    = {Hildebrand, Viet and Laschewsky, Andr{\´e} and P{\"a}ch, Michael and M{\"u}ller-Buschbaum, Peter and Papadakis, Christine M.},
  title     = {Effect of the zwitterion structure on the thermo-responsive behaviour of poly(sulfobetaine methacrylates)},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-102028},
  pages     = {13},
  year      = {2016},
  abstract  = {A series of new sulfobetaine methacrylates, including nitrogen-containing saturated heterocycles, was synthesised by systematically varying the substituents of the zwitterionic group. Radical polymerisation via the RAFT (reversible addition-fragmentation chain transfer) method in trifluoroethanol proceeded smoothly and was well controlled, yielding polymers with predictable molar masses. Molar mass analysis and control of the end-group fidelity were facilitated by end-group labeling with a fluorescent dye. The polymers showed distinct thermo-responsive behaviour of the UCST (upper critical solution temperature) type in an aqueous solution, which could not be simply correlated to their molecular structure via an incremental analysis of the hydrophilic and hydrophobic elements incorporated within them. Increasing the spacer length separating the ammonium and the sulfonate groups of the zwitterion moiety from three to four carbons increased the phase transition temperatures markedly, whereas increasing the length of the spacer separating the ammonium group and the carboxylate ester group on the backbone from two to three carbons provoked the opposite effect. Moreover, the phase transition temperatures of the analogous polyzwitterions decreased in the order dimethylammonio > morpholinio > piperidinio alkanesulfonates. In addition to the basic effect of the polymers' precise molecular structure, the concentration and the molar mass dependence of the phase transition temperatures were studied. Furthermore, we investigated the influence of added low molar mass salts on the aqueous-phase behaviour for sodium chloride and sodium bromide as well as sodium and ammonium sulfate. The strong effects evolved in a complex way with the salt concentration. The strength of these effects depended on the nature of the anion added, increasing in the order sulfate < chloride < bromide, thus following the empirical Hofmeister series. In contrast, no significant differences were observed when changing the cation, i.e. when adding sodium or ammonium sulfate.},
  language  = {en}
}
@article{FandrichBullerSchaeferetal.2015,
  author    = {Fandrich, Artur and Buller, Jens and Sch{\"a}fer, Daniel and Wischerhoff, Erik and Laschewsky, Andr{\´e} and Lisdat, Fred},
  title     = {Electrochemical characterization of a responsive macromolecular interface on gold},
  series = {Physica status solidi : A, Applications and materials science},
  volume    = {212},
  journal   = {Physica status solidi : A, Applications and materials science},
  number    = {6},
  publisher = {Wiley-VCH},
  address   = {Weinheim},
  issn      = {1862-6300},
  doi       = {10.1002/pssa.201431698},
  pages     = {1359 -- 1367},
  year      = {2015},
  abstract  = {This study reports on the investigation of a thermoresponsive polymer as a thin film on electrodes and the influence of coupling a peptide and an antibody to the film. The utilized polymer from the class of poly(oligoethylene glycol)-methacrylate polymers (poly(OEGMA)) with carboxy functions containing side chains was synthesized and properly characterized in aqueous solutions. The dependence of the cloud point on the pH of the surrounding media is discussed. The responsive polymer was immobilized on gold electrodes as shown by electrochemical, quartz crystal microbalance (QCM), and atomic force microscopy (AFM) techniques. The temperature dependent behavior of the polymer covalently grafted to gold substrates is investigated using cyclic voltammetry (CV) in ferro-/ferricyanide solution. Significant changes in the slope of the temperature-dependence of the voltammetric peak current and the peak separation values clearly indicate the thermally induced conformational change on the surface. Finally, a biorecognition reaction between a short FLAG peptide (N-Asp-Tyr-Lys-Asp-Asp-Asp-Asp-Lys-C) covalently immobilized on the polymer interface and the corresponding IgG antibody was performed. The study shows that the responsiveness of the electrode is retained after peptide coupling and antibody binding, although the response is diminished.},
  language  = {en}
}
@article{FandrichBullerWischerhoffetal.2012,
  author    = {Fandrich, Artur and Buller, Jens and Wischerhoff, Erik and Laschewsky, Andr{\´e} and Lisdat, Fred},
  title     = {Electrochemical detection of the thermally induced phase transition of a thin stimuli-responsive polymer film},
  series = {ChemPhysChem : a European journal of chemical physics and physical chemistry},
  volume    = {13},
  journal   = {ChemPhysChem : a European journal of chemical physics and physical chemistry},
  number    = {8},
  publisher = {Wiley-VCH},
  address   = {Weinheim},
  issn      = {1439-4235},
  doi       = {10.1002/cphc.201100924},
  pages     = {2020 -- 2023},
  year      = {2012},
  language  = {en}
}
@article{GambinossiSefcikWischerhoffetal.2015,
  author    = {Gambinossi, Filippo and Sefcik, Lauren S. and Wischerhoff, Erik and Laschewsky, Andr{\´e} and Ferri, James K.},
  title     = {Engineering Adhesion to Thermoresponsive Substrates: Effect of Polymer Composition on Liquid-Liquid-Solid Wetting},
  series = {ACS applied materials \& interfaces},
  volume    = {7},
  journal   = {ACS applied materials \& interfaces},
  number    = {4},
  publisher = {American Chemical Society},
  address   = {Washington},
  issn      = {1944-8244},
  doi       = {10.1021/am507418m},
  pages     = {2518 -- 2528},
  year      = {2015},
  abstract  = {Adhesion control in liquidliquidsolid systems represents a challenge for applications ranging from self-cleaning to biocompatibility of engineered materials. By using responsive polymer chemistry and molecular self-assembly, adhesion at solid/liquid interfaces can be achieved and modulated by external stimuli. Here, we utilize thermosensitive polymeric materials based on random copolymers of di(ethylene glycol) methyl ether methacrylate (x = MEO(2)MA) and oligo(ethylene glycol) methyl ether methacrylate (y = OEGMA), that is, P(MEO(2)MA(x)-co-OEGMA(y)), to investigate the role of hydrophobicity on the phenomenon of adhesion. The copolymer ratio (x/y) dictates macromolecular changes enabling control of the hydrophilic-to-lipophilic balance (HBL) of the polymer brushes through external triggers such as ionic strength and temperature. We discuss the HBL of the thermobrushes in terms of the surface energy of the substrate by measuring the contact angle at waterdecaneP(MEO(2)MA(x)-co-OEGMA(y)) brush contact line as a function of polymer composition and temperature. Solid supported polyelectrolyte layers grafted with P(MEO(2)MA(x)-co-OEGMA(y)) display a transition in the wettability that is related to the lower critical solution temperature of the polymer brushes. Using experimental observation of the hydrophilic to hydrophobic transition by the contact angle, we extract the underlying energetics associated with liquidliquidsolid adhesion as a function of the copolymer ratio. The change in cellular attachment on P(MEO(2)MA(x)-co-OEGMA(y)) substrates of variable (x/y) composition demonstrates the subtle role of compositional tuning on the ability to control liquidliquidsolid adhesion in biological applications.},
  language  = {en}
}
@article{BaussardHabibJiwanLaschewsky2003,
  author    = {Baussard, Jean-Francois and Habib-Jiwan, Jean-Louis and Laschewsky, Andr{\´e}},
  title     = {Enhanced F{\"o}rster resonance energy transfer in electrostatically self-assembled multilayer films made from new fluorescent labeled polycations},
  year      = {2003},
  language  = {en}
}
@article{SkrabaniaMiasnikovaBivigouKoumbaetal.2011,
  author    = {Skrabania, Katja and Miasnikova, Anna and Bivigou Koumba, Achille Mayelle and Zehm, Daniel and Laschewsky, Andr{\´e}},
  title     = {Examining the UV-vis absorption of RAFT chain transfer agents and their use for polymer analysis},
  series = {Polymer Chemistry},
  volume    = {2},
  journal   = {Polymer Chemistry},
  number    = {9},
  publisher = {Royal Society of Chemistry},
  address   = {Cambridge},
  issn      = {1759-9954},
  doi       = {10.1039/c1py00173f},
  pages     = {2074 -- 2083},
  year      = {2011},
  abstract  = {The absorption characteristics of a large set of thiocarbonyl based chain transfer agents (CTAs) were studied by UV-vis spectroscopy in order to identify appropriate conditions for exploiting their absorbance bands in end-group analysis of polymers prepared by reversible addition-fragmentation chain transfer (RAFT) polymerisation. Substitution pattern and solvent polarity were found to affect notably the wavelengths and intensities of the pi-pi*- and n-pi*-transition of the thiocarbonyl bond of dithioester and trithiocarbonate RAFT agents. Therefore, it is advisable to refer in end group analysis to the spectral parameters of low molar mass analogues of the active polymer chain ends, rather than to rely on the specific RAFT agent engaged in the polymerisation. When using appropriate conditions, the quantification of the thiocarbonyl end-groups via the pi-pi* band of the thiocarbonyl moiety around 300-310 nm allows a facile, sensitive and surprisingly precise estimation of the number average molar mass of the polymers produced, without the need of particular end group labels. Moreover, when additional methods for absolute molar mass determination can be applied, the quantification of the thiocarbonyl end-groups by UV-spectroscopy provides a good estimate of the degree of active end group for a given polymer sample.},
  language  = {en}
}
@misc{SchoenemannLaschewskyRosenhahn2018,
  author    = {Sch{\"o}nemann, Eric and Laschewsky, Andr{\´e} and Rosenhahn, Axel},
  title     = {Exploring the long-term hydrolytic behavior of zwitterionic polymethacrylates and polymethacrylamides},
  series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe},
  journal   = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe},
  number    = {1091},
  issn      = {1866-8372},
  doi       = {10.25932/publishup-47305},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-473052},
  pages     = {25},
  year      = {2018},
  abstract  = {The hydrolytic stability of polymers to be used for coatings in aqueous environments, for example, to confer anti-fouling properties, is crucial. However, long-term exposure studies on such polymers are virtually missing. In this context, we synthesized a set of nine polymers that are typically used for low-fouling coatings, comprising the well-established poly(oligoethylene glycol methylether methacrylate), poly(3-(N-2-methacryloylethyl-N,N-dimethyl) ammoniopropanesulfonate) ("sulfobetaine methacrylate"), and poly(3-(N-3-methacryamidopropyl-N,N-dimethyl)ammoniopropanesulfonate) ("sulfobetaine methacrylamide") as well as a series of hitherto rarely studied polysulfabetaines, which had been suggested to be particularly hydrolysis-stable. Hydrolysis resistance upon extended storage in aqueous solution is followed by ¹H NMR at ambient temperature in various pH regimes. Whereas the monomers suffered slow (in PBS) to very fast hydrolysis (in 1 M NaOH), the polymers, including the polymethacrylates, proved to be highly stable. No degradation of the carboxyl ester or amide was observed after one year in PBS, 1 M HCl, or in sodium carbonate buffer of pH 10. This demonstrates their basic suitability for anti-fouling applications. Poly(sulfobetaine methacrylamide) proved even to be stable for one year in 1 M NaOH without any signs of degradation. The stability is ascribed to a steric shielding effect. The hemisulfate group in the polysulfabetaines, however, was found to be partially labile.},
  language  = {en}
}
@article{CramerGambinossiWischerhoffetal.2015,
  author    = {Cramer, Ashley D. and Gambinossi, Filippo and Wischerhoff, Erik and Laschewsky, Andr{\´e} and Miller, Reinhard and Ferri, James K.},
  title     = {Flexible thermoresponsive nanomembranes at the aqueous-air interface},
  series = {Chemical communications},
  volume    = {51},
  journal   = {Chemical communications},
  number    = {5},
  publisher = {Royal Society of Chemistry},
  address   = {Cambridge},
  issn      = {1359-7345},
  doi       = {10.1039/c4cc07359b},
  pages     = {877 -- 880},
  year      = {2015},
  abstract  = {A synthetic pathway is described to construct thermoresponsive freestanding nanomembranes at the aqueous-air interface of a pendant drop. Dynamic control of the reaction kinetics allows formation of viscoelastic interfaces supporting anisotropic stresses and mechanical stability, which can be tuned by external stimuli.},
  language  = {en}
}
@article{PrevostWattebledLaschewskyetal.2011,
  author    = {Prevost, Sylvain and Wattebled, Laurent and Laschewsky, Andr{\´e} and Gradzielski, Michael},
  title     = {Formation of monodisperse charged vesicles in mixtures of cationic gemini surfactants and anionic SDS},
  series = {Langmuir},
  volume    = {27},
  journal   = {Langmuir},
  number    = {2},
  publisher = {American Chemical Society},
  address   = {Washington},
  issn      = {0743-7463},
  doi       = {10.1021/la103976p},
  pages     = {582 -- 591},
  year      = {2011},
  abstract  = {The aggregation behavior of catanionics formed by the mixture of cationic geminis derived from dodecyltrimethylammonium chloride (DTAC) and anionic sodium dodecylsulfate (SDS) was studied by means of phase studies and comprehensive small-angle neutron scattering (SANS) experiments at 25 degrees C and 50 mM overall concentration. The results are compared to those for the previously studied SDS + DTAC system. Various gemini spacers of different natures and geometries were used, but all of them had similar lengths: an ethoxy bridge, a double bond, and an aromatic ring binding the two DTACs in three different substitutions (ortho, meta, and para). SANS and SAXS data analysis indicates that the spacer has no large effect on the spheroidal micelles of pure surfactants formed at low concentration in water; however, specific effects appear with the addition of electrolytes. Microstructures formed in the catanionic mixtures are rather strongly dependent on the nature of the spacer. The most important finding is that for the hydrophilic, flexible ethoxy bridge, monodisperse vesicles with a fixed anionic/cationic charge ratio (depending only on the surfactant in excess) are formed. Furthermore, the composition of these vesicles shows that strongly charged aggregates are formed. This study therefore provides new opportunities for developing tailor-made gemini surfactants that allow for the fine tuning of catanionic structures.},
  language  = {en}
}
@article{StrehmelKraudeltWetzeletal.2004,
  author    = {Strehmel, Veronika and Kraudelt, Heide and Wetzel, Hendrik and Gornitz, Eckhard and Laschewsky, Andr{\´e}},
  title     = {Free radical polymerization of methacrylates in ionic liquids},
  issn      = {0065-7727},
  year      = {2004},
  language  = {en}
}
@article{StrehmelKraudeltWetzeletal.2004,
  author    = {Strehmel, Veronika and Kraudelt, Heide and Wetzel, Hendrik and G{\"o}rnitz, Eckhard and Laschewsky, Andr{\´e}},
  title     = {Free radical polymerization of methacrylates in ionic liquids},
  year      = {2004},
  language  = {en}
}
@article{StrehmelLaschewskyWetzeletal.2006,
  author    = {Strehmel, Veronika and Laschewsky, Andr{\´e} and Wetzel, Hendrik and Gornitz, Eckhard},
  title     = {Free radical polymerization of n-butyl methacrylate in ionic liquids},
  doi       = {10.1021/Ma0516945},
  year      = {2006},
  abstract  = {Ionic liquids based on imidazolium, pyridinium, and alkylammonium salts were investigated as solvents in free radical polymerization of the model monomer n-butyl methacrylate. The properties of the ionic liquids were systematically varied by changing the length of the alkyl substituents on the cations, and by employing different anions such as tetrafluoroborate, hexafluorophosphate, tosylate, triflate, alkyl sulfates and dimethyl phosphate. Results were compared to analogous polymerizations in toluene and in bulk. The solvents have no detectable influence on polymer tacticity. However, the molar masses obtained and the degree of polymerization, respectively, are very sensitive to the choice of the solvent. The degrees of polymerization are significantly higher when polymerizations were carried out in ionic liquids compared to polymerization in toluene, and can even exceed the values obtained by bulk polymerization. Imidazolium salts unsubstituted at C-2 result in an increase in the degree of polymerization of the poly(butyl methacrylate) with increasing viscosity of these ionic liquids. Methyl substitution at C-2 of the imidazolium ion results in an increase in the viscosity of the ionic liquid and in a viscosity independent degree of polymerization of the poly(butyl methacrylate). Ionic liquids based on imidazolium salts seem preferable over pyridinium and alkylammonium salts because of the higher degree of polymerization of the poly(butyl methacrylate)s obtained in the imidazolium salts. The glass transition temperatures and thermal stabilities are higher for poly(butyl methacrylate)s synthesized in the ionic liquids compared to the polymer made in toluene},
  language  = {en}
}
@article{HarmsRaetzkeFaupeletal.2010,
  author    = {Harms, Stephan and Raetzke, Klaus and Faupel, Franz and Egger, Werner and Ravello, Lori Boyd de and Laschewsky, Andr{\´e} and Wang, Weinan and M{\"u}ller-Buschbaum, Peter},
  title     = {Free volume and swelling in thin films of poly(n-isopropylacrylamide) end-capped with n-butyltrithiocarbonate},
  issn      = {1022-1336},
  doi       = {10.1002/marc.201000067},
  year      = {2010},
  abstract  = {The free volume in thin films of poly(N-isopropylacrylamid) end-capped with n-butyltrio-carbonate (nbc-PNIPAM) is probed with positron annihilation lifetime spectroscopy (PALS). The PALS measurements are performed as function of energy to obtain depth profiles of the free volume of nbc-PNIPAM films. The range of nbc-PNIPAM films with thicknesses from 40 to 200 nm is focused. With decreasing film thickness the free volume increases in good agreement with an increase in the maximum swelling capability of the nbc-PNIPAM films. Thus in thin hydrogel films the sorption and swelling behavior is governed by free volume.},
  language  = {en}
}
@article{StrehmelLaschewskyWetzel2006,
  author    = {Strehmel, Veronika and Laschewsky, Andr{\´e} and Wetzel, Hendrik},
  title     = {Homopolymerization of a highly polar zwitterionic methacrylate in ionic liquids and its copolymerization with a non-polar methacrylate},
  year      = {2006},
  abstract  = {Free radical homo- and copolymerization of the highly polar 3-(N-[2-methacryloyloxyethyl]-N,N-dimethylammonio) propane sulfonate with the nonpolar n-butylmethacrylate was investigated in the ionic liquids 1-butyl-3-methyl imidazolium tetrafluoroborate and 1-butyl-3-methylimidazolium hexafluoro phosphate, and compared to analogous polymerizations in standard solvents. Higher molar masses are obtained for the zwitterionic homopolymer when the polymerization is carried out in an ionic liquid compared to the classical reaction in water. Although homopolymerization of the sulfobetain monomer as well as of n-butylmethacrylate results in phase separation during the polymerization process, copolymerization of a stoichiometric ratio of the two monomers in the ionic liquids produced transparent gels indicating that no macrophase separation occurs. The use of ionic liquids as reaction medium improved the copolymerization behavior of the two methacrylates significantly. Whereas only minor amounts of n-butyl methacrylate were incorporated in the copolymer when synthesized in acetonitrile, the content of the non-polar monomer units in the zwitterionic copolymer approached increasingly its content in the polymerization mixture when ionic liquids were employed as solvents},
  language  = {en}
}
@misc{KoeberleLaschewsky1994,
  author    = {K{\"o}berle, Peter and Laschewsky, Andr{\´e}},
  title     = {Hybrid materials from organic polymers and inorganic salts},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-26884},
  year      = {1994},
  abstract  = {The prepaparation of amorphous, homogeneous blends of zwitterionic polymers and transition metal salts was investigated. Homogeneous miscibility was achieved in many cases up to equimolar amounts of salt, depending on the anion and cation chosen. Various analytical techniques point to a solid state solution of the inorganic ions in the polymer matrix.},
  language  = {en}
}
@misc{ElbertLaschewskyRingsdorf1985,
  author    = {Elbert, R. and Laschewsky, Andr{\´e} and Ringsdorf, H.},
  title     = {Hydrophilic spacer groups in polymerizable lipids: formation of biomembrane models from bulk polymerized lipids},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-17361},
  year      = {1985},
  abstract  = {A variety of polymerizable lipids containing a hydrophilic spacer group between the reactive group and the main amphiphilic structure have been synthesized. They were investigated in monolayers, liposomes, and multilayers. When the spacer concept was used, efficient decoupling of the motions of the polymeric chain and the amphiphilic side groups is achieved. Thus, the often found loss of the important fluid phases by polymerization is avoided. Polymeric monolayers of the spacer lipid, prepared either by polymerization in the monolayer or by spreading of prepolymerized lipid, exhibit nearly identical surface pressure-area diagrams. Most distinctly, the successful decoupling of the motions of the polymer main chain and the membrane forming amphiphilic side groups is demonstrated by the self-organization of bulk polymerized spacer lipids to polymeric liposomes. In addition, spacer lipids are able to build polymeric Langmuir-Blodgett multilayers. The decoupling of the polymer main chain and the membrane-forming amphiphilic side groups enables the deposition of already polymeric monolayers onto supports to form defined multilayers. If, alternatively, monomeric monolayers are deposited and polymerized on the support, defects in the layers due to structural changes during the polymerization are avoided by the flexible spacer group.},
  language  = {en}
}
@misc{EnzenbergLaschewskyBoeffeletal.2017,
  author    = {Enzenberg, Anne and Laschewsky, Andr{\´e} and Boeffel, Christine and Wischerhoff, Erik},
  title     = {Influence of the near molecular vicinity on the temperature regulated fluorescence response of poly(N-vinylcaprolactam)},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-400634},
  pages     = {21},
  year      = {2017},
  abstract  = {A series of new fluorescent dye bearing monomers, including glycomonomers, based on maleamide and maleic esteramide was synthesized. The dye monomers were incorporated by radical copolymerization into thermo-responsive poly(N-vinyl-caprolactam) that displays a lower critical solution temperature (LCST) in aqueous solution. The effects of the local molecular environment on the polymers' luminescence, in particular on the fluorescence intensity and the extent of solvatochromism, were investigated below as well as above the phase transition. By attaching substituents of varying size and polarity in the close vicinity of the fluorophore, and by varying the spacer groups connecting the dyes to the polymer backbone, we explored the underlying structure-property relationships, in order to establish rules for successful sensor designs, e.g., for molecular thermometers. Most importantly, spacer groups of sufficient length separating the fluorophore from the polymer backbone proved to be crucial for obtaining pronounced temperature regulated fluorescence responses.},
  language  = {en}
}
@article{MiasnikovaLaschewsky2012,
  author    = {Miasnikova, Anna and Laschewsky, Andr{\´e}},
  title     = {Influencing the phase transition temperature of poly(methoxy diethylene glycol acrylate) by molar mass, end groups, and polymer architecture},
  series = {Journal of polymer science : A, Polymer chemistry},
  volume    = {50},
  journal   = {Journal of polymer science : A, Polymer chemistry},
  number    = {16},
  publisher = {Wiley-Blackwell},
  address   = {Hoboken},
  issn      = {0887-624X},
  doi       = {10.1002/pola.26116},
  pages     = {3313 -- 3323},
  year      = {2012},
  abstract  = {The easily accessible, but virtually overlooked monomer methoxy diethylene glycol acrylate was polymerized by the RAFT method using monofunctional, difunctional, and trifunctional trithiocarbonates to afford thermoresponsive polymers exhibiting lower critical solution temperature-type phase transitions in aqueous solution. The use of the appropriate RAFT agent allowed for the preparation and systematic variation of polymers with defined molar mass, end-groups, and architecture, including amphiphilic diblock, symmetrical triblock, and triarm star-block copolymers, containing polystyrene as permanently hydrophobic constituent. The cloud points (CPs) of the various polymers proved to be sensitive to all varied parameters, namely molar mass, nature, and number of the end-groups, and the architecture, up to relatively high molar masses. Thus, CPs of the polymers can be adjusted within the physiological interesting range of 2040 degrees C. Remarkably, CPs increased with the molar mass, even when hydrophilic end groups were attached to the polymers.},
  language  = {en}
}
@article{LeporattiSczechRiegleretal.2005,
  author    = {Leporatti, S. and Sczech, R. and Riegler, H. and Bruzzano, Stefano and Storsberg, J. and Loth, Fritz and Jaeger, Werner and Laschewsky, Andr{\´e} and Eichhorn, S. and Donath, E.},
  title     = {Interaction forces between cellulose microspheres and ultrathin cellulose films monitored by colloidal probe microscopy : effect of wet strength agents},
  year      = {2005},
  language  = {en}
}
@article{GlinelJonasLaschewskyetal.2003,
  author    = {Glinel, Karine and Jonas, Alain M. and Laschewsky, Andr{\´e} and Vuillaume, Pascal Y.},
  title     = {Internally structured polyelectrolyte multilayers},
  isbn      = {3-527-30440-1},
  year      = {2003},
  language  = {en}
}
@article{AdelsbergerGrilloKulkarnietal.2013,
  author    = {Adelsberger, Joseph and Grillo, Isabelle and Kulkarni, Amit and Sharp, Melissa and Bivigou Koumba, Achille Mayelle and Laschewsky, Andr{\´e} and M{\"u}ller-Buschbaum, Peter and Papadakis, Christine M.},
  title     = {Kinetics of aggregation in micellar solutions of thermoresponsive triblock copolymers - influence of concentration, start and target temperatures},
  series = {Soft matter},
  volume    = {9},
  journal   = {Soft matter},
  number    = {5},
  publisher = {Royal Society of Chemistry},
  address   = {Cambridge},
  issn      = {1744-683X},
  doi       = {10.1039/c2sm27152d},
  pages     = {1685 -- 1699},
  year      = {2013},
  abstract  = {In aqueous solution, symmetric triblock copolymers with a thermoresponsive middle block and hydrophobic end blocks form flower-like core-shell micelles which collapse and aggregate upon heating through the cloud point (CP). The collapse of the micellar shell and the intermicellar aggregation are followed in situ and in real-time using time-resolved small-angle neutron scattering (SANS), while heating micellar solutions of a poly((styrene-d(8))-b-(N-isopropyl acrylamide)-b-(styrene-d(8))) triblock copolymer in D2O rapidly through their CP. The influence of polymer concentration as well as of the start and target temperatures is addressed. In all cases, the micellar collapse is very fast. The collapsed micelles immediately form small clusters which contain voids. They densify which slows down or even stops their growth. For low concentrations and target temperatures just above the CP, i.e. shallow temperature jumps, the subsequent growth of the clusters is described by diffusion-limited aggregation. In contrast, for higher concentrations and/or higher target temperatures, i.e. deep temperature jumps, intermicellar bridges dominate the growth. Eventually, in all cases, the clusters coagulate which results in macroscopic phase separation. For shallow temperature jumps, the cluster surfaces stay rough; whereas for deep temperature jumps, a concentration gradient develops at late stages. These results are important for the development of conditions for thermal switching in applications, e.g. for the use of thermoresponsive micellar systems for transport and delivery purposes.},
  language  = {en}
}
@article{AdelsbergerMetwalliDiethertetal.2012,
  author    = {Adelsberger, Joseph and Metwalli, Ezzeldin and Diethert, Alexander and Grillo, Isabelle and Bivigou Koumba, Achille Mayelle and Laschewsky, Andr{\´e} and M{\"u}ller-Buschbaum, Peter and Papadakis, Christine M.},
  title     = {Kinetics of collapse transition and cluster formation in a thermoresponsive micellar solution of P(S-b-NIPAM-b-S) induced by a temperature jump},
  series = {Macromolecular rapid communications},
  volume    = {33},
  journal   = {Macromolecular rapid communications},
  number    = {3},
  publisher = {Wiley-Blackwell},
  address   = {Malden},
  issn      = {1022-1336},
  doi       = {10.1002/marc.201100631},
  pages     = {254 -- 259},
  year      = {2012},
  abstract  = {Structural changes at the intra- as well as intermicellar level were induced by the LCST-type collapse transition of poly(N-isopropyl acrylamide) in ABA triblock copolymer micelles in water. The distinct process kinetics was followed in situ and in real-time using time-resolved small-angle neutron scattering (SANS), while a micellar solution of a triblock copolymer, consisting of two short deuterated polystyrene endblocks and a long thermoresponsive poly(N-isopropyl acrylamide) middle block, was heated rapidly above its cloud point. A very fast collapse together with a multistep aggregation behavior is observed. The findings of the transition occurring at several size and time levels may have implications for the design and application of such thermoresponsive self-assembled systems.},
  language  = {en}
}
@article{HuLinMetwallietal.2023,
  author    = {Hu, Neng and Lin, Li and Metwalli, Ezzeldin and Bießmann, Lorenz and Philipp, Martine and Hildebrand, Viet and Laschewsky, Andr{\´e} and Papadakis, Christine M. and Cubitt, Robert and Zhong, Qi and M{\"u}ller-Buschbaum, Peter},
  title     = {Kinetics of water transfer between the LCST and UCST thermoresponsive blocks in diblock copolymer thin films monitored by in situ neutron reflectivity},
  series = {Advanced materials interfaces},
  volume    = {10},
  journal   = {Advanced materials interfaces},
  number    = {3},
  publisher = {Wiley-VCH},
  address   = {Weinheim},
  issn      = {2196-7350},
  doi       = {10.1002/admi.202201913},
  pages     = {11},
  year      = {2023},
  abstract  = {The kinetics of water transfer between the lower critical solution temperature (LCST) and upper critical solution temperature (UCST) thermoresponsive blocks in about 10 nm thin films of a diblock copolymer is monitored by in situ neutron reflectivity. The UCST-exhibiting block in the copolymer consists of the zwitterionic poly(4((3-methacrylamidopropyl)dimethylammonio)butane-1-sulfonate), abbreviated as PSBP. The LCST-exhibiting block consists of the nonionic poly(N-isopropylacrylamide), abbreviated as PNIPAM. The as-prepared PSBP80-b-PNIPAM(400) films feature a three-layer structure, i.e., PNIPAM, mixed PNIPAM and PSBP, and PSBP. Both blocks have similar transition temperatures (TTs), namely around 32 degrees C for PNIPAM, and around 35 degrees C for PSBP, and with a two-step heating protocol (20 degrees C to 40 degrees C and 40 degrees C to 80 degrees C), both TTs are passed. The response to such a thermal stimulus turns out to be complex. Besides a three-step process (shrinkage, rearrangement, and reswelling), a continuous transfer of D2O from the PNIPAM to the PSBP block is observed. Due to the existence of both, LCST and UCST blocks in the PSBP80-b-PNIPAM(400 )film, the water transfer from the contracting PNIPAM, and mixed layers to the expanding PSBP layer occurs. Thus, the hydration kinetics and thermal response differ markedly from a thermoresponsive polymer film with a single LCST transition.},
  language  = {en}
}
@article{OrtmannAhrensMilewskietal.2014,
  author    = {Ortmann, Thomas and Ahrens, Heiko and Milewski, Sven and Lawrenz, Frank and Groening, Andreas and Laschewsky, Andr{\´e} and Garnier, Sebastien and Helm, Christiane A.},
  title     = {Lipid monolayers with adsorbed oppositely charged polyelectrolytes: Influence of reduced charge densities},
  series = {Polymers},
  volume    = {6},
  journal   = {Polymers},
  number    = {7},
  publisher = {MDPI},
  address   = {Basel},
  issn      = {2073-4360},
  doi       = {10.3390/polym6071999},
  pages     = {1999 -- 2017},
  year      = {2014},
  abstract  = {Polyelectrolytes in dilute solutions (0.01 mmol/L) adsorb in a two-dimensional lamellar phase to oppositely charged lipid monolayers at the air/water interface. The interchain separation is monitored by Grazing Incidence X-ray Diffraction. On monolayer compression, the interchain separation decreases to a factor of two. To investigate the influence of the electrostatic interaction, either the line charge density of the polymer is reduced (a statistic copolymer with 90\% and 50\% charged monomers) or mixtures between charged and uncharged lipids are used (dipalmitoylphosphatidylcholine (DPPC)/dioctadecyldimethylammonium bromide (DODAB)) On decrease of the surface charge density, the interchain separation increases, while on decrease of the linear charge density, the interchain separation decreases. The ratio between charged monomers and charged lipid molecules is fairly constant; it decreases up to 30\% when the lipids are in the fluid phase. With decreasing surface charge or linear charge density, the correlation length of the lamellar order decreases.},
  language  = {en}
}
@article{KotzevLaschewskyAdriaensensetal.2002,
  author    = {Kotzev, Anton and Laschewsky, Andr{\´e} and Adriaensens, Pieter and Gelan, Jan},
  title     = {Micellar Polymers with Hydrocarbon and Fluorocarbon Hydrophobic Chains : a Strategy to Multicompartment Micelles},
  year      = {2002},
  abstract  = {Cationic ionenes bearing hydrophobic side chains were synthesized, which behave as micellar polymers of the polysoap type. The hydrophobic chains were either hydrocarbons or fluorocarbons, or a mixture of both, in the form of statistical as well as block copolymers. These amphiphilic polymers were studied and compared with each other and with low molar mass analogous surfactants, especially with respect to their hydrophobic association in aqueous solution. The particular molecular structure of the ionenes synthesized results in polymeric surfactants with high mobility of the fluorocarbon chains. Most noteworthy, the behavior of the hydrocarbon-fluorocarbon block copolymer soaps in aqueous solution indicates microphase separation into hydrocarbon-rich and fluorocarbon-rich hydrophobic domains, thus yielding multicompartment micelles.},
  language  = {en}
}
@misc{LaschewskyPaulusRingsdorfetal.1992,
  author    = {Laschewsky, Andr{\´e} and Paulus, Wolfgang and Ringsdorf, Helmut and Schuster, A. and Frick, G. and Mathy, A.},
  title     = {Mixed polymeric monolayers and Langmuir-Blodgett multilayers with functional low molecular weight guest compounds},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-17233},
  year      = {1992},
  abstract  = {Mixed monolayers and Langmuir-Blodgett multilayers of functional low molecular weight guest compounds, especially nonlinear optical (NLO) dyes, within the matrix of an amphotropic spacer polymer have been prepared. The polymer matrix enabled the transfer of guest compounds not capable of self-organizing at the air-water interface by themselves. The structure of the LB multilayers and the transfer process were studied by small angle X-ray scattering and UV-visible spectroscopy. Good NLO coefficients were found in the mixed films.},
  language  = {en}
}
@article{StrehmelLaschewskyStoesseretal.2006,
  author    = {Strehmel, Veronika and Laschewsky, Andr{\´e} and Stoesser, Reinhard and Zehl, Andrea and Herrmann, Werner},
  title     = {Mobility of spin probes in ionic liquids},
  doi       = {10.1002/poc.1072},
  year      = {2006},
  abstract  = {The spin probes TEMPO, TEMPOL, and CAT-1 were used to investigate microviscosity and micropolarity of imidazolium based ionic liquids bearing either tetrafluoroborate or hexafluorophosphate as anions and a variation of the substitution at the imidazolium ion. The average rotational correlation times (r) obtained by complete simulation of the X-band ESR spectra of TEMPO, TEMPOL, and CAT-1 increase with increasing viscosity of the ionic liquid although no Stokes Einstein behavior is observed. This is caused by microviscosity effects of the ionic liquids shown by application of the Gierer-Wirtz theory. Interestingly, the jump of the probe molecule into the free volume of the ionic liquids is a nonactivated process. The hyperfine coupling constants (A(iso) (N-14)) of TEMPO and TEMPOL dissolved in the ionic liquids do not depend on the structure of the ionic liquids. The A(iso) (N-14) values show a micropolarity of the ionic liquids that is comparable with methylenchloride in case of TEMPO and with dimethylsulfoxide in case of TEMPOL. Micropolarity monitored by CAT-1 strongly depends on structural variation of the ionic liquid. CAT-1 dissolved in imidazolium salts substituted with shorter alkyl chains at the nitrogen atom exhibits a micropolarity comparable with dimethylsulfoxide. A significant lower micropolarity is found for imidazolium. salts bearing a longer alkyl substituent at the nitrogen atom or a methyl substituent at C-2. Copyright (c) 2006 John Wiley \& Sons, Ltd},
  language  = {en}
}