Polymer fluids

Bishop M, Ceperley D, Frisch FI L and Kales M FI 1980 Investigation of static properties of model bulk polymer fluids J Chem. Phys. 72 3228... 

Sohweizer K S and Curro J G 1997 Integral equation theories of the struoture, thermodynamios and phase transitions of polymer fluids Adv. Chem. Phys. 98 1... 

Bird, R.B., Armstrong, R. C. and Hassager, O., 1977. Dynamics of Polymer Fluids, Vol 1 Fluid Mechanics, Wiley, New York. 

Polymer-Fluid Equilibria and the Glass Transition Most polymer systems fall in the Class HI or Class V phase diagrams, and the same system can often change from one class into the other as the polymer s molecular weight changes. Most polymers are insoluble in CO9 below 100°C, yet CO9 can be quite sohible in the polymer. For example, the sorption of CO9 into silicone rubber is highly dependent upon temperature and pressure, since these properties have a large influence on the density and activity of CO9. 

Hydrodynamic interaction is a long-range interaction mediated by the solvent medium and constitutes a cornerstone in any theory of polymer fluids. Although the mathematical formulation needs somewhat elaborate methods, the idea of hydrodynamic interaction is easy to understand suppose that a force is somehow exerted on a Newtonian solvent at the origin. This force sets the surrounding solvent in motion away from the origin, a velocity field is created which decreases as ... 

Lustig, SR Camthers, JM Peppas, NA, Continuum Thermodynamics and Transport Theory for Polymer-Fluid Mixtures, Chemical Engineering Science 12, 3037, 1992. 

A polymer of the polyacrylamide type was injected as a 0.5% solution from an axially-placed nozzle at the bellmouth entrance. The experiments showed that the central thread provided drag reduction almost equivalent to premixed solutions of the same total polymer concentration flowing in the pipe. Overall concentrations of 1, 2, 4, and 20 ppm were used. Moreover, the effects were additive 2 ppm thread overall concentration plus 2 ppm premixed gave drag reductions equivalent to 4 ppm of either type. Reynolds numbers of up to 300,000 were investigated. In other experiments, a number of different polymer fluids were injected on the centerline of a water pipe-flow facility [857]. Two distinct flow regions were identified ... 

Graessley showed [40] that for a complete description of polymer fluids over the whole concentration range, i.e. from volume fraction [>—>0 to < )=1, in a thermodynamically good solvent, five distinct states of solution must be taken into account. These five states of solution are ... 

Complex (polymer) fluids can exhibit fascinating rheological properties that depend upon the history of the deformation, rather than the instantaneous state of deformation as in Newtonian fluids. As early as ad 100, the great Roman historian Cornelius Tacitus described the harvest of bitumen near a lake in The Histories V. He wrote [1] ... 

The die-swell (extrudate swell) effect describes the significant expansion of the diameter of the fluid column after exiting from a small pipe (Figure 4.3.8(b)). Some polymer fluids can have a swelling of up to two or three times the exit diameter. A simple proposition for the mechanism of the die-swell phenomenon is that while the fluid is inside the exit pipe, it is subject to a velocity shear, similar to the pipe flow with a maximum shear stress at the wall [18]. This velocity shear stretches... 

Carico, R.D. "Suspension Properties of Polymer Fluids Used in Drilling, Workover, and Completion Operations," SPE paper 5870, 1976 SPE of AIME Annual California Regional Meeting, Long Beach, April 8-9. 

Ottinger H-C (1995) Stochastic processes in polymer fluids. Springer, Berlin Heidelberg New York... 

The fundamental processes and mechanisms that control single-screw extrusion are presented in Chapters 5 through 8. These processes include solids conveying, melting, polymer fluid flow, and mixing. The analyses presented in these chapters focus on easily utilized functions needed to assess the operation of the single-screw extruder. The derivation of these relationships will be presented in detail in the appendices for those who desire to explore the theory of extrusion in more detail. 

The screw rotation analysis leads to the model equation for the extruder discharge rate. There are now two screw-rotation-driven velocities, and and a pressure-driven velocity, Pp that affect the rate. and transport the polymer fluid at right angles to one another. In order to calculate the net flow from screw rotation It Is necessary to resolve the two screw-rotation-driven velocities into one velocity, Vpi, that can be used to calculate the screw rotation-driven flow down the screw parallel to the screw axis (or centerline) as discussed in Chapter 1 and as depicted in Fig. 7.14. The resolved velocity will then be integrated over the screw channel area normal to the axis of the screw. 

In this approach the energy input into the polymer fluid is modeled as the work done by the moving surface on the fluid. The rate of work (u>.) is modeled as the product of the force F) times the velocity ([/). 

S.S. Patel and M. TirreU Measurement of Forces Between Surfaces in Polymer Fluids. Annu. Rev. Phys. Chem. 40, 597 (1989). 

H.-Ch. Ottinger, Stochastic Processes in Polymer Fluids Tools and Examples for Developing Simulation Algorithms, (Springer-Verlag, Berlin, 1996). 

A Maxwell element shows an instantaneous elastic deformation and thereafter unlimited flow. For polymers in the solid condition the latter is not realistic. For a fluid polymer it is more relevant moreover, the instantaneous elastic deformation is in accordance with the real behaviour when the stress is released a polymer fluid shows an instantaneous recoil. 

Gibbs and DiMarzio [47] (GD) first developed a systematic statistical mechanical theory of glass formation in polymer fluids, based on experimental observations and on lattice model calculations by Meyer, Flory, Huggins, and... 

Unfortunately, reliable experimental estimates of the configurational entropy are unavailable to enable explicit application of the AG model for polymer fluids. Instead, the temperature dependence of t in polymer melts is often analyzed in terms of the empirical Vogel-Fulcher-Tammann-Hesse (VFTH) equation [103],... 

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