Cationic polyelectrolytes, colloid

Cakara, D. et al.. Protonation of carboxyl latex particles in the presence of a shong cationic polyelectrolyte. Colloids Surf. A, 294, 174, 2007. 

Bruno MM, CotellaNG, Miras MC.BarberoCA (2010) A novel way to maintain resorcinol— formaldehyde porosity during drying stabilization of the sol-gel nanostructure using a cationic polyelectrolyte. Colloids Surface A 362 28-32... 

Pinkrah, V. T. Snowden, M. J. Mitchell, J. C. Seidel, J. Chowdhry, B. Z. Fern, G. R. Physicochemical properties of poly(A-isopropylacrylamide-co-4-vinylpyridine) cationic polyelectrolyte colloidal microgels. Langmuir 2003,19, 585-590. 

Shubin, V., Petrov, P. and Lindman, B., The effects of surfactants on adsorbed layers of a cationic polyelectrolyte, Colloid Polym. Sci, 272, 1590-1601 (1994). 

Colloid (or polyelectrolyte) titration . Charge may also be measured volumetrically using the principle of colloid titration which relies upon the fact that polymers of opposite charge can be stoichiometric-ally charge titrated in aqueous solution. A cationic polyelectrolyte (C) can be titrated with an anionic polyelectrolyte in the presence of an appropriate indicator (I) as follows ... 

LA Mer, V. K. Disc. Faraday Soc. 42 (1966) 248. Filtration of colloidal dispersions flocculated by anionic and cationic polyelectrolytes. 

Influent concentrations and residual concentrations of cationic surfactants, anionic surfactants, cationic polyelectrolyte, anionic polyelectrolyte, proteins, colloids, oxygen, ozone, detergents, suspended sohds, and so on, in the adsorptive bubble separation systems can be determined by the analytical methods reported in the literature (82,127-149). 

T. Sata and R. Izuo, Modification of properties of ion exchange membranes. V Structure of cationic polyelectrolyte on the surface of cation exchange membranes, Colloid Polym. Sci., 1978, 256, 757. 

Shubin, V, Samoshina, Y, Menshikova, A. and Evseeva, T., Adsorption of cationic polyelectrolyte onto a model carboxylic latex and the influence of adsorbed polvcation on the charge regulation at the latex surface. Colloid Polym. Sci., 275(7), 655,1997. 

Decher G, Schmitt J. 1992. Fine tuning of the film thickness of ultrathin multilayer films composed of consecutively alternating layers of anionic and cationic polyelectrolytes. Prog Colloid Polym Sci 89(Trends Colloid Interface Sci VI) 160 164. 

Figure 44 Repeated adsorption of anionic and cationic polyelectrolyte polymers onto colloidal particle templates followed by excavation of the core domain gives micro-Znanocapsules. Reproduced with permission from Quinn, J. F. Johnston, A. P. R. Such, G. K. etal. Chem. Soc. Rev. 2007, 36, 707-718,and Wang, Y. Angelatos, A. S. Caruso, F. Chem. Mater. 2008,20,848-858. ...

It has been shown [17] that the removal of the excess cationic polyelectrolyte led to a somewhat greater adsorption of complexes of polyallylamine hydrochloride (PAH) and polyacryhc acid (PAA) onto Si02 surfaces in water, with a net cationic charge and a degree of neutralization of 0.8, since the excess PAH diffused more rapidly to the surface and was adsorbed before the larger colloidal complexes could be adsorbed. When the PAH was removed, the complex adsorption dominated and the adsorbed amount thus increased. Similar results were found for the adsorption of cationic lattices onto cellulose fibres with an excess of cationic polyelectrolyte in solution [18], where it was found that a large excess of the cationic polyelectrolyte severely affected the amount adsorbed. Both these results show that the amount of free cationic polyelectrolyte in solution must be controlled in order to safely elucidate the mechanisms behind the adsorption of PEC onto any surface. 

Strom G, Barla P, Stenins P (1985) The formation of polyelectrolyte complexes between pine xylan and cationic polymers. Colloids Surf 13 193-207... 

Stable platinum colloids were prepared by reducing dihydrogen hexachloroplatinate H2PtCl in the presence of protective polymers. In this chapter, we report the results for several nonionic polymers and cationic polyelectrolytes and their ability to stabilize such platinum colloids. The sizes of the platinum particles were investigated by transmission electron microscopy (TEM) and found to be in the nanometer size range. The catalytic activity of these systems was tested by the hydrogenation of cyclohexene, dsp-cyclooctene, and 1-hexene. A variety of polymer-protected platinum nanoparticles showed catalytic activity, and conversions of 100 % were obtained in most cases. 

Colloid Formation. Several platinum colloids prepared by the alcohol reduction method are listed in Tables I (nonionic polymers) and II (cationic polyelectrolytes). Examples of particles diameters as determined by TEM are given in Table m. In all cases colloids were formed, and most were stable for several weeks, even months. The TEM investigations showed that the particles were in most cases evenly distributed and about 1 - 5 nm in diameter. Depending on the polymer, a range of particle sizes and narrow size distributions were obtained. 

Cationic polyelectrolytes were found to stabilize platinum colloids very well, and... 

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