Nanoasperity-Driven Reinforcement and Viscoelastic Modulation in Polymer Nanocomposites: A Coarse-Grained Molecular...

Area of Science:

• Materials Science
• Polymer Science
• Nanotechnology

Background:

• Inorganic nanofillers with nanoasperities are used in biological materials for reinforcement.
• Mechanisms of nanoasperity reinforcement in engineering polymer nanocomposites are not fully understood.

Purpose of the Study:

• Investigate the effects of nanofiller surface roughness and interfacial interactions on polymer nanocomposite mechanics.
• Understand how nanoasperities influence polymer confinement and mechanical properties.

Main Methods:

• Coarse-grained molecular dynamics simulations.
• Systematic investigation of polymethyl methacrylate (PMMA) nanocomposites with varying nanoasperity configurations and interfacial strengths.

Main Results:

• Nanoasperities induce polymer confinement, dependent on configuration and interfacial interactions.
• Strong interfacial interactions with deep nanoasperities enhance load transfer and increase elastic/shear moduli.
• Weak interactions lead to interfacial slipping, suppressing reinforcement.

Conclusions:

• Nanoasperity reinforcement results from the interplay of nanoasperity geometry, interfacial mechanics, and polymer dynamics.
• Design guidelines for tailored stiffness and damping in polymer nanocomposites can be derived from these findings.