Polyelectrolyte-modified microemulsions as new templates for the formation of nanoparticles
- The paper is focused on the formation and redispersion of monodisperse BaSO4 nanoparticles in polyelectrolyte- modified microemulsions. It is shown that a cationic polyelectrolyte of low molar mass, e.g. poly(dially1dimethylammonium chloride) (PDADMAC), can be incorporated into the individual inverse microemulsion droplets (L2 phase) consisting of heptanol, water, and an amphoteric surfactant with a sulfobetaine head group. These PDADMAC- filled microemulsion droplets can be successfully used as a template phase for the nanoparticle formation. The monodisperse BaSO4 nanoparticles are produced by a simple mixing procedure and can be redispersed after solvent evaporation without a change in particle dimensions. Dynamic and electrophoretical light scattering in combination with sedimentation experiments in the analytical Ultracentrifuge of the redispersed powder show polyelectrolyte-stabilized nanoparticles with diameters of about 6 nm. The polyelectrolyte shows a "size control effect", which can be explained by theThe paper is focused on the formation and redispersion of monodisperse BaSO4 nanoparticles in polyelectrolyte- modified microemulsions. It is shown that a cationic polyelectrolyte of low molar mass, e.g. poly(dially1dimethylammonium chloride) (PDADMAC), can be incorporated into the individual inverse microemulsion droplets (L2 phase) consisting of heptanol, water, and an amphoteric surfactant with a sulfobetaine head group. These PDADMAC- filled microemulsion droplets can be successfully used as a template phase for the nanoparticle formation. The monodisperse BaSO4 nanoparticles are produced by a simple mixing procedure and can be redispersed after solvent evaporation without a change in particle dimensions. Dynamic and electrophoretical light scattering in combination with sedimentation experiments in the analytical Ultracentrifuge of the redispersed powder show polyelectrolyte-stabilized nanoparticles with diameters of about 6 nm. The polyelectrolyte shows a "size control effect", which can be explained by the polyelectrolyte-surfactant interactions in relation to the polyelectrolyte-nanoparticle interactions during the particle growth, solvent evaporation and redispersion process. However, the approach used here opens away to produce different types of polyelectrolyte-stabilized nanoparticles (including rare metals, semiconductors, carbonates or oxides) of very small dimensions. (C) 2004 Elsevier B.V. All rights reserved…
Author details: | Joachim KoetzORCiDGND, Jennifa Bahnemann, Gordon Lucas, Brigitte TierschORCiD, Sabine KosmellaGND |
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ISSN: | 0927-7757 |
Publication type: | Article |
Language: | English |
Year of first publication: | 2004 |
Publication year: | 2004 |
Release date: | 2017/03/24 |
Source: | Colloids and Surfaces a-Physicochemical and Engineering Aspects. - ISSN 0927-7757. - 250 (2004), 1-3, S. 423 - 430 |
Organizational units: | Mathematisch-Naturwissenschaftliche Fakultät / Institut für Chemie |
Peer review: | Referiert |
Institution name at the time of the publication: | Mathematisch-Naturwissenschaftliche Fakultät / Institut für Physikalische Chemie und Theoretische Chemie |