Micromechanical model for isolated polymer-colloid clusters under tension

Area of Science:

• Materials Science
• Biomaterials Engineering
• Computational Mechanics

Background:

• Binary polymer-colloid (PC) composites are prevalent in biological load-bearing materials.
• Nature utilizes PC clusters for diverse biomaterial functions due to abundant polymers and particles.
• Limited understanding exists regarding the mechanical properties and load transfer mechanisms of these PC clusters.

Purpose of the Study:

• To propose a micromechanical model for predicting the elastic behavior of close-packed PC clusters under tension.
• To investigate the role of polymer linkers in the mechanical response of PC clusters.
• To establish a model that captures the constitutive behavior independent of local cluster geometry.

Main Methods:

• Development of a micromechanical model focusing on the backbone chain for load transfer.
• Utilizing four geometrical parameters to define six shape descriptor functions influencing deformation.
• Benchmarking model predictions against extensive coarse-grained Brownian dynamics simulations.

Main Results:

• The model successfully reproduces the average elastic behavior of PC clusters.
• The model's predictions show good agreement with simulation results across various cluster shapes and sizes.
• The model's effectiveness is demonstrated to be independent of local cluster geometry.

Conclusions:

• The proposed micromechanical model offers a simplified yet accurate method for analyzing PC cluster mechanics.
• The model's geometrical parameterization provides insights into deformation behavior.
• This model serves as a valuable add-on for multiscale simulations of nanocomposites and biomaterials.