[en] Spin-coating of isolated positively charged macromolecules onto mica in the presence of octylamine was found to be a simple and general method of stretching and aligning the macromolecular chains. The contour length and molar mass for the stretched macromolecules can be directly measured by atomic force microscopy, which makes this method a very useful analytical tool. Moreover, the molecular height is increased by codeposition with octylamine, which drastically improves the molecular resolution and allows even ultrathin polycations to be visualized. The reason for the key role of the octylamine is found in the formation of an ultrathin liquidlike alkylamine film, which reduces the surface energy of mica and weakens the interactions between the surface and the charged macromolecules.
Research center :
Center for Education and Research on Macromolecules (CERM)
Disciplines :
Materials science & engineering Chemistry
Author, co-author :
Bocharova, Vera; Leibniz Institute of Polymer Research, Dresden, Germany
Kiriy, Anton; Leibniz Institute of Polymer Research, Dresden, Germany
Stamm, Manfred; Leibniz Institute of Polymer Research, Dresden, Germany
Stoffelbach, François; Université de Liège - ULiège > Department of Chemistry > Center for Education and Research on Macromolecules (CERM)
Jérôme, Robert ; Université de Liège - ULiège > Department of Chemistry > Center for Education and Research on Macromolecules (CERM)
Detrembleur, Christophe ; Université de Liège - ULiège > Department of Chemistry > Center for Education and Research on Macromolecules (CERM)
Language :
English
Title :
Simple method for the stretching and alignment of single adsorbed synthetic polycations
BELSPO - SPP Politique scientifique - Service Public Fédéral de Programmation Politique scientifique F.R.S.-FNRS - Fonds de la Recherche Scientifique [BE] DFG - Deutsche Forschungsgemeinschaftand ESF - European Science Foundation [FR]
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