Polystyrene molecular dynamics simulation

Correlated Segmental Dynamics in Amorphous Atactic Polystyrene A Molecular Dynamics Simulation Study. 

Fig. 14. Scaled energy per unit area versus D/2hext from the molecular dynamics simulations of Murat and Grest [90] for chains of length N=100 for pacr2=0.03 (full line) compared to SFA results of Taunton et al. [37] (data points) for polystyrene in a good solvent (toluene) for a variety of molecular weights. The simulation results have been shifted vertically by an arbitrary amount to overlap with the experimental data.

Both the scaling with co and the proportionality constant, V3, are confirmed by experimental data (see Fig. 3-13). The lines in Fig. 3-13 are proportional to G and G" — computed in the nondraining limit. The agreement with data for a polystyrene of high molecular weight (M = 860,000) in theta solvents is excellent. In addition to its agreement with experimental data, the predictions of Zimm theory are supported by molecular dynamics simulations (Pierleoni and Ryckaert 1991 DUnweg and Kremer 1991). 

Harmandaris, V.A., Floudas, G., Kremer, K. Temperature and pressure dependence of polystyrene dynamics through molecular dynamics simulations and experiments. Macromolecules 44, 393-402 (2010)... 

Tamai, Y, Fukuda, M. Thermally induced phase transition of crystalline syndiotactic polystyrene studied by molecular dynamics simulation. Macromol. Rapid Common., 73,8,91-8,95 (2002). 

Milano, G, Guerra, G., Mtiller-Plathe, F. Anisotropic diffusion of small penetrants in the d crystalline phase of syndiotactic polystyrene A molecular dynamics simulation study. Chem. Mater., 14,2977-2982 (2002). 

To overcome this gap, together with the investigation of stmcture and dynamics of the adsorbed layers, respectively in Chaps. 6 and 7, here we investigated the kinetics of adsorption of polystyrene on silicon wafers covered by silicon oxide, the most commonly investigated system for studies of the deviation from bulk behavior under ID confinement. In the next sessions, after reviewing current theoretical models on adsorption of polymer chains (Sect. 5.2), we will present recent experimental results (Sect. 5.3) and the outcome of molecular dynamics simulations on a similar model system (Sect. 5.4). 

Hsieh, C. C., and Larson, R. G., Modeling hydrodynamic interaction in Brownian dynamics simulations of extensional and shear flows of dilute solutions of high molecular weight polystyrene, J. RheoL, 48, 995-1021 (2004). 

Jones DM, Walters K, WilUams PR (1987) The Extensional Viscosity of Mobile Polymer Solutions. Rheol Acta 26 20-30 McKineley GH, Sridhar T (2002) Filament-Stretching Rheome-try of Complex Huids. Annu Rev Huid Mech 34 375-415 Li L, Larson RG, Sridhar T (2000) Brownian Dynamics Simulation of Dilute Polystyrene Solutions. J Rheol 4 291-322 Gupta RK, Nguyen DA, Sridhar T (1991) Extensional Viscosity of Dilute Polystyrene Solutions Effect of Concentration and Molecular Weight. Phys Huid 12 1296-1318... 

Timm, Gilbert, Ko, and Simmons O) presented a dynamic model for an isothermal, continuous, well-mixed polystyrene reactor. This model was in turn based upon the kinetic model developed by Timm and co-workers (2-4) based on steady state data. The process was simulated using the model and a simple steady state optimization and decoupling algorithm was tested. The results showed that steady state decoupling was adequate for molecular weight control, but not for the control of production rate. In the latter case the transient fluctuations were excessive. 

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