Polymer charge density, effect parameters

Figure 11 Theoretical phase diagram of the two-zone model. Parameter 7o is the linear charge density on polyion and yn is the effective linear charge density of the cylindrical region. Phase I, weakly charged polyions Phase II, saturated condensation Phase III, unsaturated condensation. See text for details. Reproduced with permission from Dobrynin, A. V. Rubinstein, M. Prog. Polym. Sci. 2005, 30,1049-1118. Copyright 2005, Elsevier.

Figures 7 and 8 provide examples of such distributions for various effective charge densities and Debye screening lengths, respectively. The a values in Figs. 7 and 8 cover the experimental range of colloid and polyelectrolyte parameters (see Fig. 11 in [59]). For the critical parameters, the density distribution P is very broad and reaches a finite value for r oo. This corresponds to a uniform polyelectrolyte monomer density and refiects the thermodynamic equilibrium between the bound and free states of the polymer. With increasing colloid surface charge density or decreasing k [65,66], the distribution becomes more confined and...

Effect of process parameters on Theton et al. (2(X)4) the volume and surface charge density in the polymer jet, investigated. 

In summary, electrokinetic measurements combined with an advanced theory for soft surfaces is an effective tool for the comprehensive characterisafion of switchable hydrogel coatings. The accessible physicochemical parameters (distribution of polymer segment density, charge density, hydrodynamic softness, interphasial dilfuseness) complanent the results as obtained by techniques like ellipsometry or indenter measur ents. 

Overall, this stage of the process can be seen as generating a continuous current (7), which is carried by the jet, thus flowing from the needle to the collector. The current is, / = Qp, where Q indicates the jet flow rate and p is the effective volumetric charge density I may vary in a quite broad range, from the order of nA to hundreds of pA, depending on the polymer solution and experimental parameters. Especially in the early, rectilinear part... 

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