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Attraction-Enhanced Emergence of Friction in Colloidal Matter
Berend van der Meer1,2,3, Taiki Yanagishima3,4, Roel P A Dullens2,3
1Wageningen University & Research, Physical Chemistry and Soft Matter, Stippeneng 4, 6708 WE, Wageningen, The Netherlands.
Physical Review Letters
|March 7, 2025
Summary
Frictional forces in colloidal systems emerge from particle coordination. Increasing coordination slows particle movement exponentially, allowing friction control via attraction strength.
Area of Science:
- Soft Matter Physics
- Colloidal Science
- Materials Science
Background:
- Understanding microscopic friction in particulate materials is challenging due to thermal fluctuations and transient contacts.
- Interparticle friction's role in macroscopic material properties is not fully understood.
Purpose of the Study:
- To directly link particle-level frictional arrest to local coordination in colloidal systems.
- To investigate how interparticle interactions influence the formation of frictional contacts.
- To establish quantitative relationships between friction, coordination, and interparticle interactions.
Main Methods:
- Utilized an attractive colloidal model system.
- Employed simple computer simulations to model interparticle interactions and contact formation.
- Analyzed particle-level dynamics and coordination numbers.
Main Results:
- Revealed an exponential slowdown in particle orientational dynamics with increasing coordination number.
- Demonstrated that frictional interaction strength is tunable by varying attraction strength.
- Established quantitative relations connecting friction, coordination, and interparticle interactions.
Conclusions:
- Particle coordination directly dictates the emergence of microscopic friction in colloidal systems.
- Interparticle attraction strength serves as a key parameter for tuning frictional forces.
- This work provides a foundation for engineering particulate material properties through interparticle friction.
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