Soft interactions modify the diffusive dynamics of polymer-grafted nanoparticles in solutions of free polymer
| Autor: | Ali H. Slim, Ramanan Krishnamoorti, Jacinta C. Conrad, Suresh Narayanan, Ryan Poling-Skutvik |
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| Rok vydání: | 2019 |
| Předmět: |
Materials science
Polymers and Plastics Nanoparticle FOS: Physical sciences 02 engineering and technology Condensed Matter - Soft Condensed Matter 010402 general chemistry 01 natural sciences Inorganic Chemistry chemistry.chemical_compound Viscosity Dynamic light scattering Materials Chemistry chemistry.chemical_classification Quantitative Biology::Biomolecules Molecular mass Organic Chemistry Polymer Volume viscosity 021001 nanoscience & nanotechnology 0104 chemical sciences Condensed Matter::Soft Condensed Matter chemistry Chemical physics Soft Condensed Matter (cond-mat.soft) Polystyrene 0210 nano-technology Order of magnitude |
| DOI: | 10.48550/arxiv.1901.03259 |
| Popis: | We examine the dynamics of silica particles grafted with high molecular weight polystyrene suspended in semidilute solutions of chemically similar linear polymer using X-ray photon correlation spectroscopy. The particle dynamics decouple from the bulk viscosity despite their large hydrodynamic size and instead experience an effective viscosity that depends on the molecular weight of the free polymer chains. Unlike for hard-sphere nanoparticles in semidilute polymer solutions, the diffusivities of the polymer-grafted nanoparticles do not collapse onto a master curve solely as a function of normalized length scales. Instead, the diffusivities can be collapsed across two orders of magnitude in free polymer molecular weight and concentration and one order of magnitude in grafted molecular weight by incorporating the ratio of free to grafted polymer molecular weights. These results suggest that the soft interaction potential between polymer-grafted nanoparticles and free polymer allows polymer-grafted nanoparticles to diffuse faster than predicted based on bulk rheology and modifies the coupling between grafted particle dynamics and the relaxations of the surrounding free polymer. |
| Databáze: | OpenAIRE |
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