Polymer charge density

Polymer Charge Density. The effect of polymer charge density is illustrated in detail in Figure 7. For reference purposes, values obtained in the absence of the polymer are 0.4 mm/s, 38%,... 

Figure 7. Diagram illustrating the effect of polymer charge density on various flocculation responses of Na-kaolinite at pH 4.5.

Existing theories of the adsorption of polyelectrolyte allow effects of the polymer charge density, the surface charge density, and the ionic strength on the adsorption behavior to be predicted. The predicted adsorption behavior resembles that of nonionic polymers if the ionic strength is high or the polymer charge density is very low. 

Figure S.40. Charge due to adsorbed polyelectrolyte per unit of surface charge (Sa s) as a function of the total (added) amount of polyelectrolyte charge per unit surface charge (9 ). for cationic polyacrylamides of different molecular weights (expressed in K 3 kg/mole) (a) and of different polymer charge densities (b) adsorbed from salt-free solutions on anionic polyst3TFene latex. Redrawn from ref.

Abstract Two types of membrane are presented free-standing films which are formed from aqueous polyelectrolyte solutions and membranes prepared by alternating electrostatic layer-by-layer assembly of cationic and anionic polyelectrolytes on porous supports. Layer-by-layer assemblies represent versatile membranes suitable for dehydration of organic solvents and ion separation in aqueous solution. The results show that the structuring of the polyelectrolytes in the liquid films and the permeability of the multilayer membranes depends on different internal and environmental parameters, for example molecular weight, polymer charge density, ionic strength, and temperature. 

The first part concentrates on structure while the second part focuses on the permeability. Both features are highly correlated and the influence on the membrane properties of electrostatics (e.g. ionic strength, polymer charge density, pH), temperature and the molecular weight of the polymers are studied on both types of membrane. 

Ray J, Manning GS. Effect of counterion valence and polymer charge density on the pair potential of two polyions. Macromolecules 1997 30 5739-5744. 

Similar calculations for a surface that is initially charged oppositely to the polymer (charge density zp) are shown in Figure 13. The results are essentially very similar, the only difference being that the resistance now... 

Figure 3 illustrates the electro-optical effect dependence on the polymer charge density for a suspension of /3-FeOOH particles, stabilized by the adsorption of polyacrylamides with degrees of hydrolysis 3.4, 9.8, and 19.1%, respectively. The calculated electric polarizabilities y at plateau value of the corresponding adsorbed polyacrylamide T are presented in Table 1. They are of an order that is typical for all other systems described in this review—10 2S-10 32 Fm2. Values of the electric polarizability between 10 28 and 10 32 Fm2 have also been obtained for most of the polyelectrolytes investigated in solution [1,49,50]. 

Mattison K. W., Dubin P. L., Brittain I. J. complex formation between bovine serum albumin and strong poly electrolytes effect of polymer charge density. J. Phys. Chem. B 1998 102 3830-3836. 

Kogej K, Skerjanc J. Binding of cetylpyridinium cation by poly(acrylic acid). Effect of polymer charge density. Acta Chim Slov 1999 46 269-279. 

While the experiments just described address the effects of polymer charge density and molecular weight on polymer-phospholipid interactions, our work on polyanions concerns a third structured variable chain microstructure. 

Polymer charge density increase Extends polymer chains in solution under suitable conditions Decreases adsorption onto particles of the same charge sign... 

Fig. 20. Pictorial representations of polyelectrolyte adsorption under various conditions of surface charge density, polymer charge density, and ionic strength. The text discusses the specific conditions relevant to sketches a-e. Reprinted from Ref 270.

All of the states of protein-polyelectrolyte complexes referred to above may be achieved by the selection of the polyelectrolyte (PE), choice of ionic strength and pH, and control of the concentration of the macromolecular components. Most reports on the practical applications of protein-polyelectrolyte complexes concern the effects of these factors. This chapter focuses on the effects of polymer charge density, solution pH and ionic strength on protein-polyelectrolyte com-plexation discussed in recent and current research. Techniques employed in the study of protein-polyelectrolyte complexes and applications of the complex to protein separation and enzyme immobilization are also described. 

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