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http://doi.org/10.25358/openscience-1362Full metadata record
| DC Field | Value | Language |
|---|---|---|
| dc.contributor.author | Keßler, Simon | |
| dc.date.accessioned | 2017-11-05T08:43:08Z | |
| dc.date.available | 2017-11-05T09:43:08Z | |
| dc.date.issued | 2017 | |
| dc.identifier.uri | https://openscience.ub.uni-mainz.de/handle/20.500.12030/1364 | - |
| dc.description.abstract | We apply mean field continuum theories to model the assembly of particles in the co-solvent method, to which we refer as size-controlled assembly, with the objective to explain nanoparticle size dependencies on solvent mixing speeds. Our investigation starts at considering a Cahn-Hilliard equation with a Flory-Huggins-de Gennes free energy functional restricted to homopolymers. Upon modeling solvent mixing by a time dependent interaction parameter, structure formation during spinodal decomposition is analyzed. The qualitative agreement of our simulated data to both recently published Molecular Dynamics simulations and experiments indicates that size-controlled assembly can, on principle, be described by relaxation dynamics within a mean field approximation, and suggests a response of molecular organization to solvent mixing in the very early stages of phase separation to eventually determine final particle sizes. In contrast to Molecular Dynamics simulations, the Cahn-Hilliard model is able to simulate realistic mixing times and enables a perturbation approximation. The perturbation approximation does not only give an analytical interpretation to the underlying physical mechanism of size-control as a competition between molecular repulsion and interfacial tension of diffuse interfaces, but also yields a general theoretical scaling behavior that is reflected in experiments and Molecular Dynamics simulations. After introducing the notion of effective two-component models, we combine the computational efficiency of models based on time dependent interaction parameters with a more realistic description of solvent mixing by relative chemical potentials of solvents. This novel description is then shown to agree with incompressible three-component dynamics in dilute solutions that correspond to experimental conditions. Size-controlled assembly of amphiphilic diblock-copolymers is studied by inserting time dependent interaction parameters into an External Potential Dynamics model with a free energy functional from the Self Consistent Field Theory. A satisfactory analysis of particle size distributions requires the development of a new numerical integration scheme to deal with stiffness instabilities at high compressive moduli, which accelerates simulations by a factor of up to 100. Subsequent simulations indicate that neither the fundamental qualitative characteristics of particle size dependencies on mixing speeds nor the physical mechanism behind the size-control are significantly affected by copolymer architecture. Experimentally observed transitions of particle morphologies are also reproduced qualitatively. To conclude, an effective two-component model with a revised description of solvent mixing for copolymers is proposed. Based on the findings in the present work, we consider it a suitable starting point for quantitative studies of size-controlled copolymer assembly. | en_GB |
| dc.language.iso | eng | |
| dc.rights | InCopyright | de_DE |
| dc.rights.uri | https://rightsstatements.org/vocab/InC/1.0/ | |
| dc.subject.ddc | 530 Physik | de_DE |
| dc.subject.ddc | 530 Physics | en_GB |
| dc.title | Modeling size-controlled assembly of polymeric nanoparticles in interdigital micromixers | en_GB |
| dc.type | Dissertation | de_DE |
| dc.identifier.urn | urn:nbn:de:hebis:77-diss-1000016386 | |
| dc.identifier.doi | http://doi.org/10.25358/openscience-1362 | - |
| jgu.type.dinitype | doctoralThesis | |
| jgu.type.version | Original work | en_GB |
| jgu.type.resource | Text | |
| jgu.description.extent | 200 Seiten | |
| jgu.organisation.department | FB 08 Physik, Mathematik u. Informatik | - |
| jgu.organisation.year | 2017 | |
| jgu.organisation.number | 7940 | - |
| jgu.organisation.name | Johannes Gutenberg-Universität Mainz | - |
| jgu.rights.accessrights | openAccess | - |
| jgu.organisation.place | Mainz | - |
| jgu.subject.ddccode | 530 | |
| opus.date.accessioned | 2017-11-05T08:43:08Z | |
| opus.date.modified | 2017-11-10T13:05:36Z | |
| opus.date.available | 2017-11-05T09:43:08 | |
| opus.subject.dfgcode | 00-000 | |
| opus.organisation.string | FB 08: Physik, Mathematik und Informatik: Institut für Physik | de_DE |
| opus.identifier.opusid | 100001638 | |
| opus.institute.number | 0801 | |
| opus.metadataonly | false | |
| opus.type.contenttype | Dissertation | de_DE |
| opus.type.contenttype | Dissertation | en_GB |
| jgu.organisation.ror | https://ror.org/023b0x485 | |
| Appears in collections: | JGU-Publikationen | |
Files in This Item:
| File | Description | Size | Format | ||
|---|---|---|---|---|---|
 | 100001638.pdf | 37.26 MB | Adobe PDF | View/Open |