Polystyrene Sulfonate–Porphyrin Assemblies: Influence of Polyelectrolyte and Porphyrin Structure
| Autor: | Franziska Gröhn, Christian Ruthard, Michael Maskos, Ute Kolb |
|---|---|
| Rok vydání: | 2011 |
| Předmět: |
Porphyrins
Light Static Electricity Microscopy Atomic Force Porphyrin structure Polystyrene sulfonate chemistry.chemical_compound Scattering Small Angle Polymer chemistry Materials Chemistry Scattering Radiation Physical and Theoretical Chemistry Cationic polymerization Porphyrin Polyelectrolyte Nanostructures Surfaces Coatings and Films Quaternary Ammonium Compounds Neutron Diffraction Zinc chemistry Polystyrenes Spectrophotometry Ultraviolet Self-assembly Polystyrene Copper |
| Zdroj: | The Journal of Physical Chemistry B. 115:5716-5729 |
| ISSN: | 1520-5207 1520-6106 |
| Popis: | In this study, electrostatic self-assembly of different polystyrene sulfonates and a set of tetravalent cationic porphyrins is investigated. It is shown that association of linear polystyrene sulfonates of different molar masses yields finite size nanoscale assemblies that are stable in aqueous solution. Aggregates are compared to the ones of cylindrical brushes, revealing that both form assemblies in the 100 nm range with the charge ratio (molar ratio of porphyrin charges to polyelectrolyte charges) being determining, while the morphology of the resulting network-like assemblies is different for both polyelectrolyte architectures. For the smallest 8k polystyrene sulfonate, in addition, stoichiometric conditions differ. The influence of the molecular porphyrin structure was investigated by comparing meso-tetrakis(4-(trimethyl-ammonium)phenyl)porphyrin (TAPP) with its Cu(II) and Zn(II) loaded analogues and meso-tetrakis(4-N-methylpyridinium)porphyrin (TMPyP), revealing differences in stacking tendency and geometry. Additionally, the TMPyP accumulates more in the inside of the brush than the other porphyrins, likely due to the different position of its charged groups. The supramolecular nanostructures formed were characterized by UV-vis spectroscopy, light scattering, atomic force microscopy, cryo transmission electron microscopy, and small-angle neutron scattering. Results may build a valuable basis for the use of polyelectrolyte-porphyrin assemblies in medicine, catalysis, or energy conversion. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|