| Autor: |
Wolters JR; Van 't Hoff Laboratory for Physical and Colloid Chemistry, Debye Institute for Nanomaterials Science, Utrecht University , Utrecht 3584 CH, The Netherlands., Verweij JE; Van 't Hoff Laboratory for Physical and Colloid Chemistry, Debye Institute for Nanomaterials Science, Utrecht University , Utrecht 3584 CH, The Netherlands., Avvisati G; Soft Condensed Matter, Debye Institute for Nanomaterials Science, Utrecht University , Utrecht 3484 CC, The Netherlands., Dijkstra M; Soft Condensed Matter, Debye Institute for Nanomaterials Science, Utrecht University , Utrecht 3484 CC, The Netherlands., Kegel WK; Van 't Hoff Laboratory for Physical and Colloid Chemistry, Debye Institute for Nanomaterials Science, Utrecht University , Utrecht 3584 CH, The Netherlands. |
| Jazyk: |
angličtina |
| Zdroj: |
Langmuir : the ACS journal of surfaces and colloids [Langmuir] 2017 Apr 04; Vol. 33 (13), pp. 3270-3280. Date of Electronic Publication: 2017 Mar 22. |
| DOI: |
10.1021/acs.langmuir.7b00014 |
| Abstrakt: |
In this paper, we demonstrate the stabilization of polystyrene microspheres by encapsulating them with dumbbell-shaped colloids with a sticky and a nonsticky lobe. Upon adding a depletant, an effective short ranged attraction is induced between the microspheres and the smaller, smooth lobes of the dumbbells, making those specifically sticky, whereas the interaction with the larger lobes of the dumbbells is considerably less attractive due to their rough surface, which reduces the overlap volume and leaves them nonsticky. The encapsulation of the microspheres by these rough-smooth patchy dumbbells is investigated using a combination of experiments and computer simulations, both resulting in partial coverage of the template particles. For larger microspheres, the depletion attraction is stronger, resulting in a larger fraction of dumbbells that are attached with both lobes to the surface of microspheres. We thus find a template curvature dependent orientation of the dumbbells. In the Monte Carlo simulations, the introduction of such a small, curvature dependent attraction between the rough lobes of the dumbbells resulted in an increased coverage. However, kinetic constraints imposed by the dumbbell geometry seem to prevent optimal packing of the dumbbells on the template particles under all investigated conditions in experiments and simulations. Despite the incomplete coverage, the encapsulation by dumbbell particles does prevent aggregation of the microspheres, thus acting as a colloid-sized steric stabilizer. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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