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Controlled Synthesis and Fluorescence Tracking of Highly Uniform PolyN-isopropylacrylamide Microgels
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Influence of Particle Size Polydispersity on Dynamical Heterogeneities in Dense Particle Packings
Rajkumar Biswas1, Anoop Mutneja2, Smarajit Karmakar2
1Soft Condensed Matter Group, Raman Research Institute, Bangalore, India.
Summary
Increasing particle size variation can fluidize jammed suspensions, a key finding for understanding particle dynamics and improving products like paints and cosmetics.
Area of Science:
- Soft Matter Physics
- Colloidal Science
- Materials Science
Background:
- Dense particle packings exhibit correlated motion near the jamming transition.
- Dynamical heterogeneities, spatial variations in particle motion, characterize slow glassy dynamics.
Purpose of the Study:
- To investigate the effect of particle size distribution on the dynamics of dense colloidal suspensions.
- To explore the relationship between polydispersity and jamming-unjamming transitions.
Main Methods:
- Confocal microscopy to study fluorescently-labeled colloidal particles in aqueous suspensions.
- Molecular dynamics simulations to model the impact of continuous-size polydispersity (PD).
Main Results:
- Jammed suspensions can be fluidized by increasing the width of the particle size distribution.
- Simulations showed qualitative agreement with experimental findings on PD-dependent heterogeneity trends.
Conclusions:
- Particle size polydispersity influences jamming dynamics and can be used to control suspension fluidity.
- Findings offer fundamental insights into particle-scale dynamics at jamming transitions and have practical applications in formulating dense suspensions.
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