0000000000820136
AUTHOR
Ramin Djalali
Amphipolar core-shell cylindrical brushes
Methacryloyl-endfunctionalized block copolymers consisting of styrene and 2-vinylpyridine were polymerized to polyblockcomacromonomers with a much higher main chain than side chain degree of polymerization. Like homopolymacromonomers these molecules exhibit the structure of cylindrical brushes. Since the vinylpyridine block is coupled to the polymerizable group, the resulting cylindrical macromolecules exhibit a core of vinylpyridine and a shell of polystyrene, thus resembling an amphipolar unimolecular micelle of cylindrical shape. The micellar character of the structure is demonstrated by loading the cylindrical brushes with tetrachloroauric acid in toluene. Subsequent reduction leads to …
Amphipolar Core−Shell Cylindrical Brushes as Templates for the Formation of Gold Clusters and Nanowires
Methacryloyl end-functionalized block copolymers consisting of styrene and vinyl-2-pyridine were polymerized to poly(block co-macromonomer)s with a much higher main chain than side chain degree of ...
Application of the negative staining technique to both aqueous and organic solvent solutions of polymer particles
Abstract Transmission electron microscopy (TEM) imaging of several different polymers in aqueous and organic solutions using the negative staining technique is demonstrated, to emphasise the possibilities of this specimen preparation technique for polymer science. Negative stains can readily be prepared in both water and organic solvents (e.g. dimethyl formamide (DMF), dimethyl sulfoxide (DMSO) and tetrahydrofurane (THF)). Polymer particle size, size distribution and shape seen in negative stain correlates well with those of unstained materials. The particle surface and smaller particles (e.g. 10–20 nm) are more clearly defined in the presence of a negative stain. The inherent problems of s…