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Methods for the Self-integration of Megamolecular Biopolymers on the Drying Air-LC Interface
Published on: April 7, 2017
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Stratification of polymer mixtures in drying droplets: Hydrodynamics and diffusion
Michael P Howard1, Arash Nikoubashman2
1McKetta Department of Chemical Engineering, University of Texas at Austin, Austin, Texas 78712, USA.
The Journal of Chemical Physics
|August 11, 2020
Summary
Hydrodynamic interactions (HI) in drying polymer droplets determine supraparticle structure. Neglecting HI leads to stratification, while including them results in homogeneous structures, highlighting solvent effects.
Area of Science:
- Soft Matter Physics
- Polymer Science
- Computational Chemistry
Background:
- Drying droplets containing polymers can form complex supraparticle structures.
- The role of solvent dynamics and polymer-polymer interactions in stratification is not fully understood.
Purpose of the Study:
- To investigate the influence of hydrodynamic interactions (HI) on evaporation-induced stratification of polymer mixtures.
- To compare simulation results with and without explicit treatment of HI.
- To elucidate the mechanisms governing the formation of homogeneous versus stratified supraparticles.
Main Methods:
- Molecular simulations were employed to model a mixture of short and long polymer chains in a drying droplet.
- Hybrid simulations incorporating multiparticle collision dynamics (MPCD) for HI were compared with free-draining Langevin dynamics (LD) simulations.
- Phenomenological multicomponent diffusion coefficients were calculated to analyze polymer mixture behavior.
Main Results:
- Simulations including HI resulted in homogeneous dried supraparticle morphologies.
- Simulations neglecting HI (free-draining LD) led to stratified core-shell structures with short polymers forming the shell.
- The difference in morphology was attributed to the treatment of solvent and its backflow, influenced by HI.
Conclusions:
- Hydrodynamic interactions, alongside solvent backflow, are crucial for controlling polymer stratification during droplet evaporation.
- Accurate modeling of solvent dynamics is essential for predicting the final supraparticle morphology.
- This study provides insights into the self-assembly of polymers in drying systems.
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