Blome, Thomas (2022)
Thermomechanical Modeling of Amorphous Polymers Through the Glass Transition Region.
Technische Universität Darmstadt
doi: 10.26083/tuprints-00022487
Dissertation, Erstveröffentlichung, Verlagsversion
Kurzbeschreibung (Abstract)
In this thesis, we propose a novel thermodynamically consistent constitutive framework to model amorphous polymers through the glass transition region based on the internal variables approach. The model assumes the thermorheological simplicity hypothesis and covers different relaxation mechanisms related to bulk, shear, thermal stress and entropy relaxation, which are implemented by means of Prony parameters. Although the model is restricted to sufficiently slow processes, it is capable to span a wide range of temperatures of about ±75 °C around a defined reference temperature and predicts finite deformations up to engineering strain levels of 15 %. A key ingredient is the thermoviscoelastic shift function, which is defined in terms of the polymer’s potential internal energy. This allows to capture a variety of material properties intrinsic to amorphous polymers, such as physical aging and pseudo-yielding in tension and compression. In addition, we provide detailed information on the entire algorithmic solution procedure. The spatial discretization is accomplished using the finite element method, while diagonally implicit Runge-Kutta methods serve as the temporal integrator. Finally, we validate the constitutive model on four different polymeric systems, which comprise one thermoplastic (polyvinyl butyral) and three thermosets. The validation includes dilatometric and calorimetric experiments, tension and compression tests at various temperatures as well as three-point and four-point bending tests of laminated glasses with a polyvinyl butyral interlayer.
Typ des Eintrags: | Dissertation | ||||
---|---|---|---|---|---|
Erschienen: | 2022 | ||||
Autor(en): | Blome, Thomas | ||||
Art des Eintrags: | Erstveröffentlichung | ||||
Titel: | Thermomechanical Modeling of Amorphous Polymers Through the Glass Transition Region | ||||
Sprache: | Englisch | ||||
Referenten: | Gruttmann, Prof. Dr. Friedrich ; Müller, Prof. Dr. Ralf | ||||
Publikationsjahr: | 2022 | ||||
Ort: | Darmstadt | ||||
Kollation: | xiii, 133, XXXIII Seiten | ||||
Datum der mündlichen Prüfung: | 14 September 2022 | ||||
DOI: | 10.26083/tuprints-00022487 | ||||
URL / URN: | https://tuprints.ulb.tu-darmstadt.de/22487 | ||||
Kurzbeschreibung (Abstract): | In this thesis, we propose a novel thermodynamically consistent constitutive framework to model amorphous polymers through the glass transition region based on the internal variables approach. The model assumes the thermorheological simplicity hypothesis and covers different relaxation mechanisms related to bulk, shear, thermal stress and entropy relaxation, which are implemented by means of Prony parameters. Although the model is restricted to sufficiently slow processes, it is capable to span a wide range of temperatures of about ±75 °C around a defined reference temperature and predicts finite deformations up to engineering strain levels of 15 %. A key ingredient is the thermoviscoelastic shift function, which is defined in terms of the polymer’s potential internal energy. This allows to capture a variety of material properties intrinsic to amorphous polymers, such as physical aging and pseudo-yielding in tension and compression. In addition, we provide detailed information on the entire algorithmic solution procedure. The spatial discretization is accomplished using the finite element method, while diagonally implicit Runge-Kutta methods serve as the temporal integrator. Finally, we validate the constitutive model on four different polymeric systems, which comprise one thermoplastic (polyvinyl butyral) and three thermosets. The validation includes dilatometric and calorimetric experiments, tension and compression tests at various temperatures as well as three-point and four-point bending tests of laminated glasses with a polyvinyl butyral interlayer. |
||||
Alternatives oder übersetztes Abstract: |
|
||||
Status: | Verlagsversion | ||||
URN: | urn:nbn:de:tuda-tuprints-224876 | ||||
Sachgruppe der Dewey Dezimalklassifikatin (DDC): | 600 Technik, Medizin, angewandte Wissenschaften > 620 Ingenieurwissenschaften und Maschinenbau | ||||
Fachbereich(e)/-gebiet(e): | 13 Fachbereich Bau- und Umweltingenieurwissenschaften 13 Fachbereich Bau- und Umweltingenieurwissenschaften > Fachgebiete der Mechanik 13 Fachbereich Bau- und Umweltingenieurwissenschaften > Fachgebiete der Mechanik > Fachgebiet Festkörpermechanik |
||||
Hinterlegungsdatum: | 13 Okt 2022 12:02 | ||||
Letzte Änderung: | 14 Okt 2022 05:50 | ||||
PPN: | |||||
Referenten: | Gruttmann, Prof. Dr. Friedrich ; Müller, Prof. Dr. Ralf | ||||
Datum der mündlichen Prüfung / Verteidigung / mdl. Prüfung: | 14 September 2022 | ||||
Export: | |||||
Suche nach Titel in: | TUfind oder in Google |
Frage zum Eintrag |
Optionen (nur für Redakteure)
Redaktionelle Details anzeigen |