Modeling the aggregation of partially covered particles: theory and simulation

Area of Science:

• Colloid and Surface Science
• Theoretical Chemistry
• Materials Science

Background:

• Colloidal particle aggregation is crucial in various industrial processes.
• Understanding initial aggregation stages is key for controlling particle growth.
• Existing models often simplify surface interactions and coverage effects.

Purpose of the Study:

• To develop a theoretical model for the initial aggregation of partially covered colloidal particles.
• To incorporate short-range interactions and varying sticking probabilities into the model.
• To derive an analytical expression for the dimer-formation rate constant.

Main Methods:

• Developed a theoretical framework based on short-range interactions.
• Defined three distinct sticking probabilities for different collision types (bare-bare, bare-covered, covered-covered).
• Derived an analytical expression for the dimer-formation rate constant, k(11).

Main Results:

• An analytical expression for k(11) was successfully deduced as a function of surface coverage and sticking probabilities.
• Theoretical predictions from the model showed strong agreement with simulation data.
• The model effectively captures the initial stages of aggregation for partially covered particles.

Conclusions:

• The developed theoretical model provides a robust framework for understanding initial colloidal aggregation.
• The model's accuracy, confirmed by simulations, highlights its utility in predicting aggregation dynamics.
• This work advances the understanding of surface coverage effects on particle aggregation processes.