Formation mechanism of nanotubes comprising layers of PbS nanoparticles in polymer-surfactant solutions
Kyriacou, Kyriacos C.
SourceJournal of colloid and interface science
Google Scholar check
MetadataShow full item record
The crystallization of PbS in aqueous solutions containing the surfactant sodium dodecyl sulfate (SDS) and hydrophilic polymers resulted in a novel type of metastable nanotubes, the walls of which consist of layers of ordered PbS nanoparticles, apparently separated by layers of surfactant molecules. Information on the mechanism of formation of these structures was obtained by focusing on the roles of the polymer, and of the insoluble lead dodecyl sulfate (Pb(DS)2) present in the system. TEM investigations of the early stages of crystallization revealed the coexistence of PbS and Pb(DS)2 precipitates, the latter being surprisingly important for nanotube formation, and allowed to follow the evolution of layered structures from combination of the two types of crystals. Six different hydrophilic polymers have been used, which interact with SDS with varying strengths. Surprisingly, and in contrast to previous hypotheses, layered nanostructures were observed in all polymer solutions, regardless of the strength of polymer-surfactant interactions. This indicates that, although the presence of a polymer is necessary, polymer-SDS interactions are not a driving force for the formation of the layered structures and nanotubes. On the contrary, the interactions between the polymer chains and the growing particles appear to be of the utmost importance. Results presented here can be interpreted in terms of two alternative mechanisms for layered nanostructure and nanotube formation. © 2006 Elsevier Inc. All rights reserved.
Showing items related by title, author, creator and subject.
Covalent amphiphilic polymer networks Patrickios, Costas S.; Georgiou, Theoni K. (2003)The recent literature on chemically cross-linked amphiphilic polymer networks is reviewed. The main subjects covered are network synthesis, characterization, modeling and applications. Special mention is made to more modern ...
Degradable polymer networks and star polymers based on mixtures of two cleavable dimethacrylate crosslinkers: Synthesis, characterization, and degradation Themistou, Efrosyni; Patrickios, Costas S. (2009)Mixtures of two cleavable dimethacrylate crosslinkers, the hydrolyzable di(methacryloyloxy-1-ethoxy)methane (DMOEM) and the thermolyzable 1,1-ethylenediol dimethacrylate (EDDMA), were used for the preparation of neat ...
Shear-induced nanometer and micrometer structural responses in nanocomposite hydrogels Loizou, Elena; Porcar, L.; Schexnailder, P.; Schmidt, G.; Butler, P. (2010)The structural responses of a polymer-clay nanocomposite hydrogel to an imposed shear field are investigated from the nanometer to the micrometer length scales. The effects of polymer molecular weight and concentration of ...