MSc Students Presentations - George Papadopoulos
Abstract (Περίληψη)
Through this work, blends of ring and linear poly(ethylene oxide) (PEO) molecules have been studied, a widely used polymer, with well-known characteristics. The main focus was on ring PEO molecules, as they exhibit material properties that are very different from those of linear analogues, due to the absence of chain ends and their closed-loop structure.
We have performed molecular dynamics (MD) simulations of melt systems consisting of a small number of long ring poly(ethylene oxide) (PEO) molecules immersed in a host matrix of linear PEO chains, following a recent neutron spin echo spectroscopy study (Goossen et al., Phys. Rev. Lett. 2015, 115, 148302). The results are compared with the experimental data of the work above, and include a thorough study on the structure, the conformational properties and the dynamics of the simulated blends. These regard calculations such as the segmental and the diffusion dynamics, the dynamic structure factor and a comparison with the Rouse model, emphasizing on their dependence on the length of the host linear chains. Interestingly, in unentangled matrices ring chains swell and their diffusion dynamics become evidently faster. Our results are supported by a geometric analysis of topological interactions between the linear and the ring molecules, which reveals significant threading of all rings by the linear chains. In most cases, each ring is simultaneously threaded by a large number of linear chains. As a result, ring dynamics at times longer than τe is completely dictated by the release of the topological restrictions imposed by these threading events. Our topological analysis did not indicate any effect of the few rings on the statistics of the network of primitive paths of the host linear chains.
Speakers Short CV (Σύντομο Βιογραφικό Ομιλητή)
STUDIES
2016 – Today
Department of Physics of National and Kapodistrian University of Athens
Undergraduate studies
2014 – Today
Department of Chemical Engineer, University of Patras
Master of Science with specialization on
«Process Simulation, Optimization and Control»
2009 – 2014
Department of Chemical Engineer, University of Patras
Grade: 7,21/10
PUBLICATIONS IN PEER-REVIEWED JOURNALS
George D. Papadopoulos, Dimitrios G. Tsalikis and Vlasis G. Mavrantzas. «Microscopic Dynamics and Topology of
Polymer Rings Immersed in a Host Matrix of Longer Linear Polymers: Results from a Detailed Molecular Dynamics
Simulation Study and Comparison with Experimental Data»
Polymers 2016, 8(8), 283; doi: 10.3390/polym8080283
THESIS
«Study of the thermodynamic interaction of a quantum system of a 4-state harmonic oscillator with two heat baths», under the supervision of prof. Vl. Mavrantzas
LANGUAGES
English (fluent) - Proficiency Michigan
German (intermediate) – Grundstufe
COMPUTER SKILLS
Advanced knowledge of programming language FORTRAN, Microsoft Windows, Word, Excel, PowerPoint, UNIX, Origin, ΜathType, WolframAlpha, ASPEN HYSYS.
Knowledge and application of molecular simulation methods (Molecular Dynamics), focusing on polymers.
Familiar with MATLAB, Maple, Mathematica, GAMS.