h1

% IMPORTANT: The following is UTF-8 encoded.  This means that in the presence
% of non-ASCII characters, it will not work with BibTeX 0.99 or older.
% Instead, you should use an up-to-date BibTeX implementation like “bibtex8” or
% “biber”.

@PHDTHESIS{Strauch:1022281,
      author       = {Strauch, Christian},
      othercontributors = {Richtering, Walter and Reščič, Jurij},
      title        = {{M}odeling and {M}onte {C}arlo simulations of polyampholyte
                      microgels with complex structures},
      school       = {RWTH Aachen University},
      type         = {Dissertation},
      address      = {Aachen},
      publisher    = {RWTH Aachen University},
      reportid     = {RWTH-2025-09914},
      pages        = {1 Online-Ressource : Illustrationen},
      year         = {2025},
      note         = {Veröffentlicht auf dem Publikationsserver der RWTH Aachen
                      University 2026; Dissertation, RWTH Aachen University, 2025},
      abstract     = {Microgels are three-dimensional crosslinked polymer
                      networks, ranging in size from nanometers to micrometers,
                      that are swollen by a solvent. They exhibit responsiveness
                      to external stimuli such as temperature, pH, ionic strength,
                      and magnetic fields. For biomedical applications, such as
                      drug delivery, polyampholyte microgels are particularly
                      promising due to their ability to safely transport drugs to
                      target sites and release them through charge reversal
                      triggered by pH changes. This thesis uses Metropolis Monte
                      Carlo simulations to investigate the ionization and swelling
                      behavior of polyelectrolyte and polyampholyte microgels and
                      their capacity to take up guest molecules. A parallelized
                      algorithm developed in this work enables the simulation of
                      more complex topologies, such as core-shell structures, and
                      allows for simulations at higher ionic strengths. The
                      microgel models used in this thesis are based on a
                      coarse-grained model, providing results in qualitative
                      agreement with experimental findings. By systematically
                      varying parameters like pK values, microgel concentration,
                      and ionic strength around a reference system, the influence
                      of these parameters on macroscopic properties, such as the
                      degree of ionization and the radius of gyration, is
                      determined. Additionally, the simulations provide insights
                      into properties that are difficult to obtain experimentally,
                      such as the degree of ionization for both acids and bases
                      within the same microgel, and microscopic information,
                      including local ionization within the microgels. Simulations
                      of core-shell polyampholyte microgels show that the width of
                      the U-shaped swelling curve as a function of pH depends on
                      the relative dissociation constants of acidic and basic
                      monomers. The addition of salt narrows this swelling
                      transitions. Furthermore, microgel swelling correlates
                      approximately linearly with the total network charge.
                      Simulations involving polyelectrolyte and polyampholyte
                      microgels with various types of guest molecules demonstrate
                      the capability of these microgels to take up such molecules.
                      In particular, the model for oligopeptide uptake in
                      polyelectrolyte microgels shows promise for future
                      investigations in combination with experimental studies.
                      Finally, the constant pH method in the canonical ensemble is
                      critically evaluated following criticisms about the approach
                      being implicitly grand-canonical. While titration curves
                      obtained with this method and the reaction ensemble method
                      show significant differences for colloidal particles, they
                      differ only at low degrees of ionization for polyelectrolyte
                      microgels. The results demonstrate that the constant pH
                      method provides a reliable and practical approach for the
                      microgels simulated in this thesis.},
      cin          = {153310 / 150000},
      ddc          = {540},
      cid          = {$I:(DE-82)153310_20140620$ / $I:(DE-82)150000_20140620$},
      typ          = {PUB:(DE-HGF)11},
      doi          = {10.18154/RWTH-2025-09914},
      url          = {https://publications.rwth-aachen.de/record/1022281},
}