Polyethylene oxide solution

Fig. 4.2.11 Shear viscosity versus shear rate data for a 1 % aqueous polyethylene oxide) solution. SynT bols same as in Figure 4.2.10.

Capillary coating can also stabilize the migration times and resolutions. This is in particular necessary in the case of peptide and protein analysis, because proteins tend to stick to capillary walls. Often low-concentration polyethylene oxide solutions are recommended as well as dynamic bilayer coating formed by a non-covalent adsorption of polybrene and polyvinylsulfonate (PVS). Due to the stability of the EOF, the variation of intra- and intercapillary migration time was less than 1% relative standard deviation (RSD) with basic analytes and peptides. 

Fig. 30a-d. Polymerization of methyl methacrylate by high speed stirring of polyethylene oxide solution, a) effect of monomer concentration on polymerization rate (PEO 4 g/100 ml, stirring speed 30000 rpm. b) effect of monomer (MMA) concentration on intrinsic viscosity of reaction mixture (PEO 4 g/100 ml, stirring speed 30000 rpm, solvent benzene, c) effect of PEO concentration on polymerization rate, d) effect of PEO concentration on intrinsic viscosity of reaction mixture (Stirring speed 30000 rpm)... 

Finally, it might be noted that colloids may be concentrated by a slight modification of the dialysis procedure. The liquid against which the colloid of interest is being dialyzed may itself be a concentrated colloid. With aqueous dispersions, for example, polyethylene oxide solutions may be used as the second colloid. 

Gold PI, Amar PK, Swaidan BE (1973) Friction reduction degradation in dilute polyethylene oxide) solutions J Appl Polym Sci 17 333... 

In order to illustrate the specific material properties of polymers, we compare a viscous fluid (silicone oil) with a viscoelastic shear thinning fluid (aqueous polyethylene oxide solution). These fluids are used as model fluids in order to show the flow behavior limits for polymer melts, which corresponds to the behavior of a viscous fluid at very low shear rates and to the behavior of a shear thinning fluid at very high shear rates. 

A similar degradation test was conducted with a concentrated solution of 1500 wppm polyethylene oxide [35], Analysis of test results reveals good agreement with the polyacrylamide solutions. In particular, the critical Weissenberg values for the polyethylene oxide solution are of the same order as those for the polyacrylamide solution. 

In this same spirit, it is proposed that the intermediate values of the heat transfer coefficient lying between the newtonian value and the lower asymptotic limit be estimated from the pipe flow correlation shown in Fig. 10.28 [114]. This approach should give reasonable estimates, at least for aqueous polyacrylamide and polyethylene oxide solutions. 

Figure J. a. The opposed jets. The polymer solution is sucked into the jets along the symmetry axis, o represents the stagnation point in the center of the flow field, b. The flow field visualized by light scattered at 90° from tracer particles, c, A birefringent line between the jets for a 0.1% solution of atactic polystyrene (a-PS). d. The perturbed flow field during flare formation in a semiddute polyethylene oxide solution.

The poly(NIPAM) dispersions containing polyethylene oxide solutions showed no instability at any polymer concentration. Despite carrying out the experiments in 0.01 mol dm 3 NaCl where the electrical double layer surrounding the particles, 1/k is less than lOnm, thus allowing adsorbed polymer chains to bridge, no instability was observed. Further at higher polymer concentrations there was no evidence of any depletion flocculation operative in the system. 

Extensional flow and structure-property relationships may also be studied by birefiringence. A particularly interesting application from transient flow is presented in Figure 2, where phenomena such as overshoot and ringing are observed (3). In this example we see results for 1.5% polyethylene oxide solution for three different velocity gradients. Birefringence detects the presence of an overshoot,... 

The frequency of Kaiman vortices is reduced in polyethylene oxide solutions but both amplitude and frequency increase in guar gum solutions... 

Antonova, N., and Lazarov, Z., Hemorheological and hemodynamic effects of high molecular weight polyethylene oxide solutions, Clinical Hemorheology a. Microcirculation, 2004, vol. 30, pp. 381-390. 

Average pressure profiles (clockwise and counterclock wise) for a 3% polyethylene oxide solution. From Olabisi and Williams (1972). 

FIGURE 7.6 Flow curves for polyethylene oxide solutions in water. The lines throngh the data are model predictions. (Data from Rodriguez, F., Trans. Soc. RheoL, 10, 169, 1966.)... 

Figure 8.5 Osmotic pressure of aqueous polyethylene oxide solutions at 20°C. (From Ref. 9.)...

Calculate the coUigative properties of aqueous polyethylene oxide solutions and compare the results with the polystyrene-toluene system data given in Table 8.1. 

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