Concave polymer brushes inwardly grafted in spherical cavities

Area of Science:

• Polymer Physics
• Soft Matter Physics
• Computational Biophysics

Background:

• Polymer brushes confined to curved surfaces, like membranes and vesicles, exhibit unique behaviors compared to planar systems.
• Understanding these structures is crucial for applications in nanotechnology and biomaterials.

Purpose of the Study:

• Investigate the structure and scaling properties of inwardly curved polymer brushes under good solvent conditions.
• Compare simulation results with existing theoretical predictions for varying polymer molecular weights and grafting densities.
• Analyze the impact of strong surface curvature on brush conformation and properties.

Main Methods:

• Extensive molecular dynamics simulations were performed.
• Studied polymer chains with different molecular weights (N) and grafting densities (σg).
• Examined structures under strong surface curvature (R⁻¹).

Main Results:

• Characterized critical radius (R*) separating weak and compressed brush regimes.
• Analyzed radial monomer/chain-end density profiles, bond orientation, and brush thickness.
• Identified a new scaling relationship for normal pressure: P_N(R)∝σ_g⁴, independent of chain stiffness (κ).

Conclusions:

• Molecular dynamics simulations validate and extend theoretical predictions for curved polymer brushes.
• The identified pressure scaling offers new insights into confined polymer systems.
• Results provide a foundation for designing and controlling polymer brush behavior on curved interfaces.