Modeling the drying of polymer coatings

Area of Science:

• Materials Science
• Chemical Engineering
• Polymer Science

Background:

• Drying of polymer coatings involves complex phase transitions and stress development.
• Understanding the interplay between polymer diffusion and phase separation is crucial for predicting coating performance.

Purpose of the Study:

• To develop a predictive model for the drying phenomenon in polymer coatings.
• To investigate the influence of polymer diffusion and porous skin properties on coating stress.

Main Methods:

• A two-phase model was developed, distinguishing between a polymer-lean (liquid) and polymer-rich (solid) phase.
• Biot's theory was applied to model the porous skin and calculate coating stress.
• Governing equations were solved using a finite difference scheme.

Main Results:

• The model successfully predicts polymer concentration profiles, showing good agreement with experimental data.
• Polymer diffusion and skin permeability were identified as key factors influencing coating stress.

Conclusions:

• The developed model provides a robust framework for understanding polymer coating drying.
• The study highlights the importance of considering phase behavior and material properties for stress prediction in coatings.