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1

Computer Simulation of the Dynamic Behavior of Double Polymer Brush-Solvent Systems

Hałagan K., Banaszak M., Jung J., Polanowski P., Sikorski A.

Computational Methods in Science and Technology

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2021

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Vol. 27, No. 4

141--149

EN

Opposing polymer brush systems were investigated by computer simulations. In a coarse-grained model, chains were restricted to a face-centered cubic lattice with the excluded volume interactions only. The macromolecules were grafted onto two parallel impenetrable surfaces. The dynamic properties of these systems were studied by means of Monte Carlo simulations. The Dynamic Lattice Liquid model and a highly efficient parallel machine ARUZ were employed, which enabled studying large systems at long time scales. The influence of the surface grating density on the system dynamic was shown and discussed. It was demonstrated that the self-diffusion coefficient of solvent depended strongly on the grafting density.

2

The Comparison of Monte Carlo Algorithms Applied for Off-Lattice Models of Polymer Chains

Kuriata A., Gront D., Sikorski A.

Computational Methods in Science and Technology

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2016

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Vol. 22, No. 4

179--185

EN

We designed two simplified models of macromolecular systems. Model chains were built of united atoms (statistical segments): the first one was a bead-spring model while in the second one beads were connected by bonds of constant length. The only potential introduced was the excluded volume and thus the system was athermal. Monte Carlo simulations of these models were carried out using Metropolis-like algorithms appropriate for each model: the one-bead displacement and the backrub algorithm. The scaling analysis of the chain’s static and dynamic properties was carried out. The universal behavior of the chain’s properties under consideration was found and discussed. The efficiency of both algorithms was compared and discussed.

3

One-dimensional chain with hernias

Drzewiński A.

Prace Naukowe Instytutu Matematyki i Informatyki Politechniki Częstochowskiej

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2005

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Vol. 4, nr 1

38-44

EN

The density-matrix renormalization-group method has been applied to the modified d = 1 Rubinstein-Duke model for polymer dynamics, where hernias are considered. This simple model demonstrates the crossover from reptation to Rouse dynamics.

4

Dielectric relaxations in hydrogen bonded supramolecular polymers

Wübbenhorst M., Folmer B., Turnhout J., Sijbesma R. P., Meijer E.

Prace Naukowe Instytutu Technologii Organicznej i Tworzyw Sztucznych Politechniki Wrocławskiej. Konferencje

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2001

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Vol. 50, nr 23

25-29

EN

The molecular and cooperative dynamics of supramolecular linear polymers and networks, which are formed by self association of di- or tri-functional monomers exhibiting quadruple hydrogen bonds, was studied by broadband dielectric spectroscopy (DRS) in the frequency range from 10-2 - 10-9 Hz. In all materials, from a linear polymer to a dense network, four dielectric relaxations were found and lebeled [gamma], [beta], [alfa] and [gamma]*. Two of them were assigned to the local dynamics ([gamma]) of the supramolecular chains as well as to the dynamics glass transition ([alfa]) as typical for an amorphus polymer. In contrast, the [beta] and [alfa]* relaxations were identified as "chemical" relaxations, the fast one reflecting the reversible junction dynamics of hydrogen bonded units in the glassy state. The slow [alfa]* - relaxation was found to be the dielectric manifestation of chain breaking/remaking above the glass transition driven by the cooperative segmental motions.

PL

Badano dynamikę molekularną i współzależną supramolekularnych polimerów liniowych i sieci polimerowych utworzonych przez auto-asocjację monomerów di- tri-funkcyjnych wykazujących kwadrupolowe wiązania wodorowe, za pomocą szerokopasmowej spektroskopii dielektrycznej (DRS) w zakresie częstości 10-2 - 10-9 Hz. Znalezino cztery rodzaje dielektrycznych relaksacji zarówno w polimerach liniowych jak i w sieciach, które oznaczono jako [gamma], [beta], [alfa] i [alfa]*. Dwie z nich jako typowe dla polimerów amorficznych, zostały przypisane lokalnej dynamice łańcuchów supramolekularnych ([gamma]) jak również dynamicznemu zeszkleniu ([alfa]). Relaksacje [beta] i [alfa]* były zidentyfikowane jako "chemiczne"; szybsza odzwierciedlała odwracalną dynamikę przyłączy grup związanych wiązaniem wodorowym w stanie szklistym. Powolną relaksację [alfa]* uznano jako dielektryczną manifestacją procesu odrywania się i łączenia łańcuchów powyżej temperatury zeszklenia, powodowaną przez współzależne ruchy segmentów łańcucha.