Polyelectrolyte complex preparation

Michaels et al.50 53) reported the chemical and physical properties of the polyelectrolyte complex of NaSS-PVBMA. This complex is used as a membrane in various fields. Polyelectrolyte complexes prepared by casting homogeneous solutions of ternary-solvent systems mentioned above are transparent and amorphous. Dried polyelectrolyte complexes are hard materials whereas wetted ones are rubber-like or skin-like. The polyelectrolyte complex with an equimolar composition is neutral whereas that with a non-equimolar composition can display ion-exchange properties. The range of the water content depends on the excess of polycation or polyanion in the complex. [Pg.38]

For the preparation of spray-dried polyelectrolyte complexes, the polyanion was dissolved in dilute NH4HCO3 solution and mixed with the chitosan carbamate solution just before spray-drying. The excess NH4HCO3 decomposed thermally between 60 and 107 °C on the other hand, the carbamate function released carbon dioxide under the effect of the temperature at which the spray-drier was operated, thus regenerating chitosan at the moment of the polyelectrolyte microsphere formation (Fig. 5). [Pg.177]

Reihs T, Muller M, Lunkwitz K (2004) Preparation and adsorption of refined polyelectrolyte complex nanoparticles. J Colloid Interface Sci 271 69-79... [Pg.57]

Kang HS, Park SH, Lee YG et al (2007) Polyelectrolyte complex hydrogel composed of chitosan and poly(y-glutamic acid) for biological application Preparation, physical properties, and cytocompatibility. J Appl Polym Sci 103 386-394... [Pg.60]

Kawashima, Y., et al. 1985. Novel method for the preparation of controlled-release theophylline granules coated with a polyelectrolyte complex of sodium polyphosphate-chitosan. J Pharm Sci 74 264. [Pg.67]

Yancheva E, Paneva D, Maximova V et al. (2007) Polyelectrolyte complexes between (cross-linked) (V-carboxyethylchitosan and (quatemized) poly[2-(dimethylamino)ethyl methacrylate] preparation, characterization, and antibacterial properties. Biomacromolecules... [Pg.216]

Electrochemically Prepared Polyelectrolyte Complex of Polypyrrole and a Flavin-Containing Polyanion... [Pg.169]

SCHOO CHALLA Electrochemically Prepared Polyelectrolyte Complex 165... [Pg.170]

SCHOO CHALLA ElectrochemicaUy Prepared Polyelectrolyte Complex 173... [Pg.178]

Polyelectrolyte complexes can be prepared in a desired range of mass, size and structure density. The behavior of the PECs can be controlled by external parameters such as the ionic strength, the pH of the medium or the temperature. Therefore, such complexes should be of great interest as potential carrier systems for drugs, enzymes, or DNA because charged species can easily be integrated into the complex particles. [Pg.124]

Buchhammer HM, Lunkwitz K (1998) Preparation and Characterization of Different Polyelectrolyte Complexes and their Application as Flocculants. Colloid Polym Sci 276 125... [Pg.109]

Resins of polyelectrolyte complexes may be prepared commercially by at least four methods compiled in Table 752. ... [Pg.37]

The polyelectrolyte complex is prepared by mixing poly(sodium styrenesulfonate) (NaSS) and partially quaternized poly(4-vinylpyridine) (QPVP) at [NaSS]/[cationic site of QPVP] = 1.0... [Pg.101]

It has been attempted to perform template polymer syntheses without using biological sources. Concepts focus on the formation of a complex between monomer molecules and a present macromolecule [4,480], This way the monomer will get preorganized and the polymerization is supposed to follow a zip mechanism controlled by the length and the configuration of the template polymer, offering replication of the molecular weight and control of the stereo structure. Polymerization of acrylic acid in the presence of poly(ethyleneimine), N-vinylimidazole/ poly(methacrylic acid) or acrylonitrile with poly(vinylacetate) have been described [469,470,471,472,473]. Recently the preparation of solid polyelectrolyte complexes from chitosan and sodium-styrenesulfonate has been reported [481]. [Pg.156]

Polyelectrolyte complexes are very promising materials for preparing semi-permeable membranes of definite permeability and selectivity The methods of preparation and the properties of membranes made of polyelectrolyte complexes based on strong polyelectrolytes, e.g. poly(sodium sterene sulfonate) and poly(vinylbenzyl-trimethyl ammonium chloride) were described These membranes may be applied for reverse osmosis in the desalting of sea-water, for dialysis and ultrafiltration in purifications and concentration of water solutions containing coUoids or micro-and macroparticles ... [Pg.140]

The membranes produced from polyelectrolyte complexes on the basis of weak polyel trolytes, e.g. poly(carboxylic adds) (PAA and PMAA) and polyamines [poly(2-N,N-dimethylaminoethyl methacrylate), polyethylaiepiperidine, polyethyl-enepy( rasine, polyethylenimine] have been prepared and used in dialysis and ultrafiltration. Permeability coeffidents of membranes made from poly electrolyte complexes are much higher (4 and 20 times, resp.) in comparison with the cellulose-bas membranes (Cuprophane, Film 1(M)). [Pg.140]

Interactions between macromolecules can occur in formulations, for example when preparations are mixed. They can be put to good advantage in the synthesis of novel compounds. Polyethyleneimine and poly(acrylic acid) form a polyelectrolyte complex with saltlike bonds as shown in (V). If the complex is heated as a film, interchain amide bonds are formed between the groups which formed electrostatic links. The nonionised -COOH and -NH groups in the chain are the points of structural defects in the film. [Pg.287]

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