Mesoscale modelling of polymer aggregate digestion.

Area of Science:

• Biophysics
• Polymer Science
• Rheology

Background:

• Biopolymer aggregates, or boluses, are stabilized by physical cross-links.
• Understanding aggregate stability is crucial for processes like digestion and material science.

Purpose of the Study:

• To investigate the break-up dynamics of cross-linked biopolymer aggregates.
• To determine the key parameters controlling aggregate stability and dispersion.
• To explore the effects of fluid flow and chemical breakdown on aggregate evolution.

Main Methods:

• Mesoscale simulations were employed to model polymer aggregate behavior.
• A simplified model was used to analyze the impact of chemical breakdown.
• The influence of shear flow, characterized by the Weissenberg number, was investigated.

Main Results:

• Aggregate stability is primarily governed by the linking bead fraction and interaction energy.
• Chemical breakdown disperses aggregates that would otherwise remain stable.
• Three distinct regimes of aggregate behavior under shear flow were identified based on the Weissenberg number.
• A synergistic effect between shear flow and chemical breakdown was observed at high reaction rates.

Conclusions:

• Biopolymer aggregate stability is a complex interplay of physical and chemical factors.
• Shear flow can effectively break down aggregates, with critical regimes identified.
• Combined mechanical and chemical degradation offers enhanced aggregate disruption.