Polymer blends Monte Carlo simulations

Monte Carlo simulations, which include fluctuations, then yields Simulations of a coarse-grained polymer blend by Wemer et al find = 1 [49] in the strong segregation limit, in rather good... 

M. Muller, K. Binder, and W. Oed (1995) Structural and thermodynamic properties of interfaces between coexisting phases in polymer blends - a monte-carlo simulation. J. Chem. Soc. Faraday Trans. 91, pp. 2369-2379... 

In recent work Jerry and Dutta [176] reanalyzed, with the mean field approach, conditions [8] of the second order wetting transition. They have found that critical wetting transition must be accompanied by a prerequisite phenomenon of an enrichment-depletion duality it is expected that the surface is enriched in the given component when bulk composition ( )M is below a certain value Q and is depleted in the same component for >Q. Such an effect, easily predicted by simple lattice theory [177] and observed in Monte Carlo simulations [178, 179], has been very recently determined by us for a real polymer blend [175] (see Sect. 3.1.2.4). 

The picture presented above is not complete as it neglects non-mean field behavior of polymer blends in the temperature range close to Tc [149]. The Ising model predicts phase diagrams of thin films, which are more depressed and more flattened than those yielded by mean field approach (as marked in Fig. 31d). Both effects were shown by Monte Carlo simulations performed by Rouault et al. [150]. In principle, critical regions of phase diagrams cannot be described merely by a cross-over from a three- to two-dimensional (for very thin films) situation. In addition, a cross-over from mean field to Ising behavior should also be considered [6,150]. 

Very recent Monte Carlo simulations and self consistent mean field calculations [223] have shown that wetting properties might be reflected in the phase diagram of a blend confined between symmetric selective surfaces Close to Tw a convex curvature is exhibited by the phase diagram on the side poor in preferentially adsorbed polymer. Also the temperature dependence of Ap changes around the wetting point Tsv. 

In this paper, Monte Carlo simulation studies will be discussed which provide insight into the underlying factors that affect the ability of a copolymer to strengthen and interface and compatibilize a polymer blend. The interpretation ofthese results will then be correlated to the experimental evidence that currently exists in the literature. It is expected that the results of this work will provide important fundamental information on the underlying physics that govern the interfacial behavior of copolymers. In turn, this information can be utilized to develop processing schemes by which materials can be efficiently created from polymer mixtures with optimized and tunable properties. 

Monte Carlo simulation of the compatibilization of polymer blends with linear... 

In Fig. 11.3, we made a comparison between the binodals obtained from dynamic Monte Carlo simulations (data points) and from mean-field statistical thermodynamics (solid lines). First, one can see that even with zero mixing interactions B = 0, due to the contribution of Ep, the binodal curve is still located above the liquid-solid coexistence curve (dashed lines). This result implies that the phase separation of polymer blends occurs prior to the crystallization on cooUng. This is exactly the component-selective crystallizability-driven phase separation, as discussed above. Second, one can see that, far away from the liquid-solid coexistence curves (dashed lines), the simulated binodals (data points) are well consistent... 

Chapter 1.17 by Kurt Binder describes the present state of art in the field of Monte Carlo simulation approaches in polymer science. Both static and dynamic properties of single maaomolecules of various chemical architearrres and systems containing many polymers (solutions, melts, blends, etc.) are considered. 

Figure 15 (a) Phase diagram of a binary polymer blend N= 32) as obtained from Monte Carlo simulations of the bond fluctuation model. The upper curve shows the binodais in the infinite system the middle one corresponds to a thin film of thickness D=2.8/ e and symmetric boundary fields [wall = 0.16, both of which prefer species A (capillary condensation). The lower curve corresponds to a thin film with antisymmetric surfaces (interface localization/delocalization). The arrow marks the location of the wetting transition. Full circles mark critical points open circles/dashed line denotes the triple point, (b) Coexistence curves in the (T, A/y)-plane. Circles mark critical points, and the diamond indicates the location of the wetting transition temperature. It is indistinguishable from the temperature of the triple point. Adapted from Muller, M. Binder, K. Phys. Rev. 2001, 63, 021602. ... 

Figure 16 Composition profiles of the interface between two laterally coexisting phases in a thin film with symmetric surface interactions as obtained from Monte Carlo simulations of a binary polymer blend. A-rich regions are shaded light B-rich regions are shaded dark, (a) Corresponds to a temperature above the wetting transition temperature T S.STwet-There are A-enrichment layers in the B-rich region, and the AB interface does not approach the wall. The thickness, h, of the A-rich surface enrichment layers in the B-rich phase is indicated by an arrow.

Benchmark Monte Carlo simulations of a different class of athermal polymer mixtures have recently been carried out by Weinhold et al. An equimolar = 0.5), constant-volume binary blend was considered. The polymers were modeled as semiflexible, tangent bead chains of equal degrees of polymerization, N, interacting via a purely hard-core potential... 

Abstract This topic reviews random walk Monte Carlo simulation models of charge transport in DSSC. The main electrmi transport approaches used are covered. Monte Carlo methods and results are explained, addressing the continuous time random walk model developed for transport in disordered materials in the context of the large number of trap states present in the electron transporting material. Multiple timescale MC models developed to look at the morphology dependence of electron transport are described. The concluding section looks at future applications of these methods and the related MC models for polymer blend cells. 

Malik, R Hall, C.K., and Genzer, J. (2011) Phase separation dynamics for a polymer blend compatibilized by protein-like copolymers A Monte Carlo simulation. Macromolecules, 44, 8284—8293. 

Mark JE, Sen TZ, Kloczkowski A. Some Monte Carlo simulations on nanoparticle reinforcement of elastomers. In Karger-Kocis J, Fakirov S, editors. Nano- and micromechanics of polymer blends and composites. New York Hanser Publishers 2009. p. 519-44. 

Monte Carlo Simulations for Complex Fluids Monte Carlo Simulations for Liquids Polymer Brushes Polymers Melts and Blends. 

Figure 8 Comparison of PRISM predictions (solid lines) to Monte Carlo simulation data for the pair correlation functions in blends of hard-chain branched (open circles) and linear (filled circles) polymers...

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