Atomistic and Mesoscopic Simulations of the Interfacial Dynamics of Polymer Melts

Σγούρος, Αριστοτέλης

dc.contributor.author	Σγούρος, Αριστοτέλης	el
dc.date.accessioned	2019-07-03T07:45:17Z
dc.date.available	2019-07-03T07:45:17Z
dc.date.issued	2019-07-03
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/48967
dc.identifier.uri	http://dx.doi.org/10.26240/heal.ntua.3088
dc.rights	Αναφορά Δημιουργού-Μη Εμπορική Χρήση 3.0 Ελλάδα	*
dc.rights	Αναφορά Δημιουργού-Μη Εμπορική Χρήση-Όχι Παράγωγα Έργα 3.0 Ελλάδα	*
dc.rights.uri	http://creativecommons.org/licenses/by-nc-nd/3.0/gr/	*
dc.subject	πολυαιθυλένιο	el
dc.subject	προσομοίωση	el
dc.subject	μοριακή δυναμική	el
dc.subject	διεπιφάνειες	el
dc.subject	ρεολογία	el
dc.subject	interfaces	en
dc.subject	polyethylene	el
dc.subject	simulation	el
dc.subject	multiscale	el
dc.subject	rheology	el
dc.title	Atomistic and Mesoscopic Simulations of the Interfacial Dynamics of Polymer Melts	en
dc.contributor.department	Εργαστήριο Επιστήμης και Τεχνικής των Υλικών (Co.M.S.E.)	el
heal.type	doctoralThesis
heal.secondaryTitle	Ατομιστικές και Μεσοσκοπικές Προσομοιώσεις της Διεπιφανειακής Δυναμικής Πολυμερικών Τηγμάτων	el
heal.classification	Polymer Physics	en
heal.classification	Multiscale Simulations	en
heal.language	en
heal.access	campus
heal.recordProvider	ntua	el
heal.publicationDate	2019-03-07
heal.abstract	The advent of models and advanced computational tools coupled with the exponential growth of computational resources over the past decades, have aided substantially in guiding the design of enhanced polymer materials of major technological importance in a broad range of industrially relevant applications. Atomistic simulations have assisted a great deal in the understanding of elusive microscopic phenomena manifesting themselves at polymer interfaces and of their mechanisms and in establishing structure-property relations; they have a drawback, however, namely that the computational cost they entail increases rapidly when considering processes involving high molar mass polymers of industrial relevance, with relaxation times far exceeding the accessible simulation times. Continuum simulation methods, on the other hand, have been really successful in modeling macroscopic phenomena; however, one has to make careful assumptions regarding the parameterization of a continuum model, especially when the examined phenomenon is sensitive to mechanisms exhibiting large time scale separations. The accurate modeling of complex rheological phenomena exhibiting sensitivity to mechanisms manifesting themselves over a vast range of time- and length-scales has motivated the development of multiscale strategies comprising several levels of description, each level focusing on a specific window of time and length scales, receiving input from more detailed levels and providing input to coarser ones. The current thesis develops a multiscale simulation strategy for homogeneous and inhomogeneous polymer melts and polymer/solid interfaces over a broad range of molar masses, under quiescent and flow conditions. The multiscale simulation strategy comprises the following steps: a) The finer level of description entails atomistic simulations of unentangled and entangled polymer melts allowing, for the estimation of several thermodynamic, structural and dynamical properties on the segment and on the chain level. b) The atomistic trajectories are mapped onto mesoscopic, coarse-grained representations through a well-defined mapping procedure. The mesoscopic representations are then analyzed and the extracted information is used as an input for the mesoscopic simulations of the multiscale approach. c) The parameters of the mesoscopic models are derived from the atomistic level of description through a bottom-up parameterization procedure. The mesoscopic models are developed “hand in hand” with atomistic simulations and the validity of the mesoscopic observables is assessed through comparisons with atomistic ones along the overlapping molar mass regimes. The multiscale strategy has been applied to linear monodisperse polyethylene melts and can be easily extended to describe other types of polymers and interfaces. The advantage of this multiscale strategy is that it allows for the characterization of several thermodynamic (i.e., interfacial free energies, local stress), structural (ie. short- and long-range size, shape and orientation of chain segments and entire chains) and dynamical (diffusion, viscosity) properties under quiescent and flow conditions, across a very broad molar mass regime.	en
heal.sponsor	I gracefully acknowledge financial support through the following projects: “Multiscale Simulations of Complex Polymer Systems” (MuSiComPS) by the Limmat Foundation, Zurich, Switzerland; “Multiscale Simulations of Soft Matter Systems”, ΓΓΕΤ AWARDS, Project 2006Σ01330025. Furthermore, computational resources made available by the Greek Research & Technology Network (GRNET) on the National HPC facility –ARIS– under project IDs pr003013 (MSMS) and pr002023 (HMSM) are gratefully acknowledged. This work was further supported by the LinkSCEEM-2 project, funded by the European Commission under the 7th Framework Programme through Capacities Research Infrastructure, INFRA-2010-1.2.3 Virtual Research Communities, Combination of Collaborative Project and Coordination and Support Actions (CP-CSA) under grant agreement no RI-261600 CYTERA with project IDs: lspre372, lspre386 and lspre412.	en
heal.advisorName	Θεοδώρου, Θεόδωρος (Δώρος) Ν.	el
heal.committeeMemberName	Παπαδόπουλος, Γεώργιος	el
heal.committeeMemberName	Χαριτίδης, Κωνσταντίνος	el
heal.committeeMemberName	Καλόσακαs, Γεώργιος	el
heal.committeeMemberName	Σιγάλας, Μηχαϊλ	el
heal.committeeMemberName	Μαυραντζάς, Βλάσης	el
heal.committeeMemberName	Νταουλάς, Κωνσταντίνος	el
heal.academicPublisher	Σχολή Χημικών Μηχανικών	el
heal.academicPublisherID	ntua
heal.numberOfPages	296
heal.fullTextAvailability	true