Polymers molecular dynamics simulation

Phys. Condens. Matter, 15, S1127 (2003). Self-Motion and the a-Relaxation in Glass-Forming Polymers. Molecular Dynamic Simulation and Quasielastic Neutron Scattering Results in Polyisoprene. 

Figure 2.4 Simulated trajectories of helium, oxygen and methane molecules during a 200-ps time period in a poly(dimethylsiloxane) matrix [9]. Reprinted with permission from S.G. Charati and S.A. Stern, Diffusion of Gases in Silicone Polymers Molecular Dynamic Simulations, Macromolecules 31, 5529. Copyright 1998, American Chemical Society...

S.G. Charati and S.A. Stern, Diffusion of Gases in Silicone Polymers Molecular Dynamic Simulations, Macromolecules 31, 5529 (1998). 

In Fig. 10.18 we compare the INS spectra of oriented films of pristine /ra -polyacetylene and in the sodimn and potassium doped states. Even with poor resolution, differences are apparent between the spectra. The most striking is the gap at 80 cm that appears in the doped polymers. Molecular dynamics simulations show that the translational mode that peaks at 80 cm in the pristine sample shifts down to 64 cm in the doped samples and the mode at 160 cm shifts up to 230 cm. ... 

Charati, S. G. Stern, S. A., Diffusion of Gases in Silicone Polymers Molecular Dynamics Simulations. Macromolecules 1998, 31, 5529-5535. 

Sokal A D 1995 Monte Carlo and Molecular Dynamics Simulations in Polymer Science ed K Binder (New York Oxford University Press) oh 3... 

Kremer K and Grest G S 1990 Dynamics of entangled linear polymer melts a molecular-dynamics simulation J Chem. Phys. 92 5057... 

Applications of Ab-Initio Molecular Dynamics Simulations in Chemistry and Polymer Science... 

D. W. Noid, B. G. Sumpter, B. Wunderlich and G. A. Pfeffer, Molecular dynamics simulations of polymers Methods for optimal Fortran programming , J. Comput. Chem., 11(2), 236-241, 1990. 

Since this behavior is universal, it is obvious that the simplest simulation models which contain the essential aspects of polymers are sufficient to study these phenomena. Two typical examples of such models are the bond fluctuation Monte Carlo model and the simple bead-spring model employed in molecular dynamics simulations. Both models are illustrated in Fig. 6. 

Fig. 7 gives an example of such a comparison between a number of different polymer simulations and an experiment. The data contain a variety of Monte Carlo simulations employing different models, molecular dynamics simulations, as well as experimental results for polyethylene. Within the error bars this universal analysis of the diffusion constant is independent of the chemical species, be they simple computer models or real chemical materials. Thus, on this level, the simplified models are the most suitable models for investigating polymer materials. (For polymers with side branches or more complicated monomers, the situation is not that clear cut.) It also shows that the so-called entanglement length or entanglement molecular mass Mg is the universal scaling variable which allows one to compare different polymeric melts in order to interpret their viscoelastic behavior. 

D. Y. Yoon, M. Vacatello, G. D. Smith. Simulation studies of polymer melts at interfaces. In K. Binder, ed. Monte Carlo and Molecular Dynamics Simulations in Polymer Science. New York Oxford University Press, 1995, pp. 422-A15. 

I. Bitsanis, G. Hadziioannou. Molecular dynamics simulations of the structure and dynamics of confined polymer melts. J Chem Phys 92 3827-3847, 1990. 

K. Binder. Monte Carlo and molecular dynamics simulations of amorphous polymers. In J. Bicerano, ed. Computational Modeling of Polymers. New York Marcel Dekker, 1992, pp. 221-295. 

G. Grest, K. Kremer. Molecular dynamics simulation for polymers in the presence of heat bath. Phys Rev A 55 3628-3631, 1986. 

Whenever the polymer crystal assumes a loosely packed hexagonal structure at high pressure, the ECC structure is found to be realized. Hikosaka [165] then proposed the sliding diffusion of a polymer chain as dominant transport process. Molecular dynamics simulations will be helpful for the understanding of this shding diffusion. Folding phenomena of chains are also studied intensively by Monte Carlo methods and generalizations [166,167]. 

Dimitrov, D. 1., Milchev, A. and Binder, K (2007) Polymer brushes in solvents of variable quality Molecular dynamics simulations using explicit solvent./. Chem. Phys., 127, 084905. 

Binder K (ed) (1995) Monte Carlo and molecular dynamics simulations in polymer science. Oxford University Press, Oxford... 

Yoon DY, Vacatello M, Smith GD (1995) In Binder K (ed) Monte Carlo and Molecular Dynamics Simulation in Polymer Science. Oxford Univ Press, Oxford, pp 433-475... 

In the perspective discussed in the present contribution, bundle formation occurs within the amorphous phase and in undercooled polymer solutions. It does not imply necessarily a phase separation process, which, however, may occur by bundle aggregation, typically at large undercoolings [mode (ii)]. In this case kinetic parameters relating to chain entanglements and to the viscous drag assume a paramount importance. Here again, molecular dynamics simulations can be expected to provide important parameters for theoretical developments in turn these could orient new simulations in a fruitful mutual interaction. 

Lemak, A. S. and Balabaev, N. K. (1996). Molecular dynamics simulation of a polymer chain in solution by collisional dynamics method, J. Comput. Chem., 17, 1685-1695. 

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