SKM 2021 – wissenschaftliches Programm

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CPP: Fachverband Chemische Physik und Polymerphysik

CPP 6: Poster Session II

CPP 6.19: Poster

Dienstag, 28. September 2021, 17:30–19:30, P

Crystallization of oligomers in melts between two hard walls: flat histogram Monte Carlo simulation — •Evgeniia Filimonova, Timur Shakirov, and Viktor Ivanov — Martin-Luther-University Halle-Wittenberg, Institute of Physics, 06099, Halle, Germany

We study conformational properties of short polymer chains in melts between two hard walls. Our final goal is to reveal physical factors which are responsible for a particular scenario of surface-induced polymer crystallization (e.g., the nucleation and growth or the 1st order prefreezing). We use a coarse-grained model and perform flat histogram Monte Carlo (MC) simulations based on the stochastic approximation Monte Carlo (SAMC) algorithm. We analyse different order parameters: nematic orientational order parameter, bond orientation order parameters (Steinhardt parameters), hexagonal order parameter (which shows a quasi-two-dimensional stacking of chain cross sections in a plane perpendicular to the director). We see the nematic transition (formation of rotator phase) upon cooling, followed by a crystallization transition. We are able to observe a coexistence of an isotopic structure in the center of the film with ordered structures at the walls at intermediate values of energies (in microcanonical analysis). We are able to localise the transition points between different pseudo-phases quite precisely. Financial support of the International Graduate School AGRIPOLY supported by the European Social Fund (ESF) and the Federal State Saxony-Anhalt is acknowledged.