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Soft matter: from shapes to forces on the nanoscale
Derek Y C Chan1, Ofer Manor2, Jason N Connor3
1Particulate Fluids Processing Centre, Department of Mathematics and Statistics, The University of Melbourne, Parkville, VIC 3010, Australia. D.Chan@unimelb.edu.au O.Manor@pgrad.unimelb.edu.au and Department of Mathematics, National University of Singapore, 117543, Singapore. matchand@nus.edu.sg.
Soft Matter
|September 10, 2020
Summary
We found that dynamic surface forces on soft matter, like fluid drops, can be measured by analyzing deformations far from the interaction zone. This provides a new way to understand forces in colloidal systems.
Area of Science:
- Soft matter physics
- Colloidal science
- Surface physics
Background:
- Soft matter systems deform under external forces.
- Understanding inter-particle forces is crucial in colloidal systems.
- Dynamic surface forces play a key role in soft matter behavior.
Purpose of the Study:
- To demonstrate the link between dynamic surface forces and far-field deformations in soft matter.
- To introduce a new method for determining forces between soft particles.
- To illustrate this concept using a fluid drop interacting with a solid wall.
Main Methods:
- Analyzing hydrodynamic drainage flow between a fluid drop and a solid wall.
- Considering repulsive or attractive dissimilar electrical double layer interactions.
- Deducing forces from the analysis of the drop surface geometry outside the interaction zone.
Main Results:
- Dynamic surface forces are directly linked to far-field deformations.
- A fluid drop's surface geometry change predicts interaction forces.
- This method applies to systems with hydrodynamic and electrical double-layer interactions.
Conclusions:
- A novel paradigm for measuring inter-particle forces in soft matter systems is presented.
- Force determination can be achieved through simple geometric analysis of deformations.
- This approach simplifies the study of colloidal interactions.
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