Polymers affecting dynamics

The concentration-dependent models attribute the observed pressure dependence of the solubility and diffusion coefficients to the fact that the presence of sorbed gas in a polymer affects the structural and dynamic properties of the polymer, thus affecting the sorption and transport characteristics of the system (3). On the other hand, in the dual-mode model, the pressure-dependent sorption and transport properties arise from a... 

Figure 9.18 gives one more example of how interaction affects dynamic mechanical properties. Two polymers were tested with various concentrations of alumina. Polystyrene was almost unaffected by various concentrations of filler. Sulfonated polystyrene interacts more strongly with its filler than polystyrene which contributes to increase in Tg." ... 

A major incentive of this article will be to stress the complicating traits of the membrane environment on effective proton transport and fuel cell performance. The polymer affects distribution and structme of water and dynamics of protons and water molecules at multiple scales. In order to describe the conductivity of the membrane, one needs to take into account explicit polymer-water interactions at molecular level, interfacial phenomena at polymer-water interfaces at mesoscopic scale and the statistical geometry and topology of randomly distributed aqueous and polymeric domains at macroscopic scale. 

Figures 13 and 14 demonstrate how the state of a substrate surface and a peculiar interfacial (polymer-substrate and/or polymer-air) dynamics affect the thermal behavior of thin polymer films.

P.B. Smith Temperature affects dynamics, dynamics affect NMR linewidths, and dynamics also affect flow. These effects are observed not only in linear polymers but in crosslinked polymers as well, highly crosslinked polymers, too, I might add, where I just don t see how you can have flow. I think flow is a function of the molecular dynamics, as are the NMR linewidths. The molecular dynamics give rise to both parameters rather than flow causing NMR line narrowing. 

Unlike linear polymers, topological entanglements in cross-Hnked polymers affect not only dynamic, but also equihbrium mechanical properties. The equilibrium shear modulus at the temperature above glass transition consists of two components CTx estimated from the classical theory and Oy connected with the network topology [29]. The share of topological component depends on the chemical cross-hnking degree [48]. 

The flow behavior of the polymer blends is quite complex, influenced by the equilibrium thermodynamic, dynamics of phase separation, morphology, and flow geometry [2]. The flow properties of a two phase blend of incompatible polymers are determined by the properties of the component, that is the continuous phase while adding a low-viscosity component to a high-viscosity component melt. As long as the latter forms a continuous phase, the viscosity of the blend remains high. As soon as the phase inversion [2] occurs, the viscosity of the blend falls sharply, even with a relatively low content of low-viscosity component. Therefore, the S-shaped concentration dependence of the viscosity of blend of incompatible polymers is an indication of phase inversion. The temperature dependence of the viscosity of blends is determined by the viscous flow of the dispersion medium, which is affected by the presence of a second component. 

In the dynamic Monte Carlo simulations described earlier, we used a crystalline template to suppress supercooling (Sect. A.3). If this template is not present, there will be a kinetic interplay between polymer crystallization and liquid-liquid demixing during simulations of a cooling run. In this context, it is of particular interest to know how the crystallization process is affected by the vicinity of a region in the phase diagram where liquid-liquid demixing can occur. 

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