Polyelectrolyte gel-surfactant complexes

A surprising result was obtained for both cationic gel-anionic surfactant systems The metal-containing samples appear not less ordered than the initial polyelectrolyte gel-surfactant complexes despite the diminished amplitudes of the peaks. For the PDADMACl-SDBS system, the average distance between... 

As can be seen from the discussion above, the polyelectrolyte gel-surfactant complexes present interesting hybrid metal-polymer nanocomposites, allowing a vast variety of incorporated metals and metal-polymer-surfactant structures. The limitations of these systems are their heterogeneous character (insoluble in any media) and excessive sensitivity to external parameters (pH, temperature, etc.). 

C. Monteux, C.E. WiUiams, J. Meunier, O. Anthony, and V. Bergeron Adsorption of Oppositely Charged Polyelectrolyte/Surfactant Complexes at the Air/Water Interface Formation of Interfacial Gels. Langmuir 20, 57 (2004). 

It has been shown that the exchange of counter ions for the ions of a surfactant can induce a sharp collapse of the polyelectrolyte gel. Simultaneously, a very effective absorption of surfactants from the solution is observed. Complexes of the networks with surfactants possess the ability to solubilize different organic substances. The later fact is of important practical interest, for example for removing surfactants and impurities from water. 

Hirata M, Yamada Y, Kokufuta E. Effects of pH and alkyl sulfate surfactants on swelling equilibria for a cationic polyelectrolyte gel from poly-(ethyleneimine). In Schmitz K, ed. Macro-ion Characterization from Dilute Solutions to Complex Fluids. ACS Symp Ser, No 548. Washington DC Amer Chem Soc, 1994 493-498. 

Among solid polymer nanostructures, two types of systems will be described (a) complexes of polyelectrolyte gels with surfactants and (b) crosslinked polymers containing nanopores or nanocavihes. 

Gels sensitive to electric field were also obtained using the process of reversible complex formation between a polyelectrolyte gel and an oppositely charged surfactant. The complex formation is accompanied by surfactant ion aggregation to micelles, which results in gel contraction at the site of complexation (Figure 22). By using an electric field to direct surfactant binding selectively to one side of the gel, one can induce contraction and curvature of a strip of gel. ° ... 

Olga E. Philippova s main research interests are polyelearolyte and ionomer behavior of polymer gels, linear and cross-linked polyelectrolytes with associating hydrophobic groups, polymer gel/surfactant interactions, interpolymer complexes, and polymer gels with entrapp l linear stiff-chain macromolecules. 

Our list of future directions cannot be complete without mentioning polyelectrolyte gels, polyelectrolyte brushes [192-195] (polyelectrolytes grafted to a surface), and complexation of polyelectrolytes with colloids [196-200], dendrimers [201], surfactants, and proteins. We anticipate serious... 

The formation of these DNA gel particles constitutes an example of strong associative phase separation. An indication of the strength of this interaction is the formation of a stronger film (or skin) constituted by the polyelectrolyte-surfactant complex. Preliminary results of S AXS measurements have supported the existence of an ordered structure formed on the hydrated skin of the obtained particles. SEM images of the cross-section of the particles have given evidence for the existence of a shell structure, its formation being more pronounced in the case of ss-DNA. The capsule shells obtained may be considered as physical networks in which surfactant micelles form polycationic-multianionic electrostatic complexes as crosslink points. 

A detailed study of the structure of the aggregates of the ionic surfactants in polyelectrolyte networks was presented in Refs. [66,68]. The dynamics of the changes in the microenvironment of the fluorescent probe, pyrene, in slightly crosslinked networks of poly(diallyldimethylammonium bromide) (PDADMAB) during diffusion of sodium dodecyl sulfate (SDS) in the gel phase has been investigated by means of fluorescence spectroscopy. In Ref. [66], an analogous investigation was reported for complexes formal by the sodium salt of PMAA with cetyltrimethylammonium bromide (CTAB). 

Ray B, El Hasri S, Gnenet JM. Effect of polymer tacticity on the molecnlar strnctnre of polyelectrolyte/surfactant stoichiometric complexes in solntions and gels. Enr Phys J E 2003 11 315-323. 

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