Modeling Self-Rollable Elastomeric Films for Building Bioinspired Hierarchical 3D Structures.

Area of Science:

• Materials Science
• Mechanical Engineering
• Biomedical Engineering

Background:

• Rolled structures from elastomeric bilayers are crucial for advanced applications.
• Existing models like Timoshenko's formula have limitations in predicting behavior under large deformations and multi-turn rolling.

Purpose of the Study:

• To develop an innovative model for predicting inner and outer radii in rolled polydimethylsiloxane (PDMS) bilayers.
• To improve upon Timoshenko's formula by incorporating inter-layer friction for multi-turn rolling.
• To explore applications in cell/tissue engineering and bioinspired materials.

Main Methods:

• Development of a predictive model for rolled elastomeric bilayers.
• Incorporation of friction effects between layers during multi-turn rolling.
• Experimental validation using PDMS bilayers with varied initial strain and thickness.

Main Results:

• The model accurately predicted experimental data for inner and outer radii, with errors below 2% for the outer diameter under high friction.
• The model demonstrated superior performance compared to existing literature, especially for multi-turn rolling scenarios.
• Successful prediction of complex 3D bioinspired hierarchical elastomeric microstructures with errors smaller than 18%.

Conclusions:

• The proposed model enhances the prediction of rolled structure geometry, particularly for elastomeric bilayers undergoing large deformations.
• The model's ability to account for friction broadens its applicability in materials design.
• The findings open new avenues for fabricating and modeling bioinspired materials for diverse applications, including tissue engineering.