Multiscale Analysis of the Highly Stretchable Carbon-Based Polymer Strain Sensor.

Area of Science:

• Materials Science
• Nanotechnology
• Mechanical Engineering

Background:

• Carbon nanoparticles (CNPs)-filled polymers are promising for strain sensing in wearable electronics, flexible skin, and health monitoring.
• Accurate simulation of their electromechanical behavior is essential for device design and performance prediction.
• Existing methods may not fully capture the microstructural influences on sensing mechanisms.

Purpose of the Study:

• To propose and validate a multiscale analysis method for simulating CNPs-filled polymers as strain sensors.
• To establish a link between microstructural characteristics and macroscopic electromechanical responses.
• To enable effective prediction of material behavior with varying parameters.

Main Methods:

• Development of a microscale representative volume element (RVE) model for CNPs-filled polymers using an improved nearest-neighbor algorithm.
• Finite element analysis (FEA) to extract junction width variations between adjacent CNP aggregates.
• Simplification of the composite as a random resistor network, with resistance determined by junction widths, to model electrical properties.

Main Results:

• The multiscale method successfully correlates microstructural junction widths with the overall resistance variation under strain.
• Numerical simulations and experimental results for silicone elastomer filled with CNPs showed good agreement.
• The method effectively predicts the electromechanical responses of CNPs-filled polymers across different filling amounts and material parameters.

Conclusions:

• The proposed multiscale analysis method provides a robust framework for understanding the strain-sensing mechanism in CNPs-filled polymers.
• This approach enables accurate prediction of electromechanical behavior, facilitating the development of advanced sensors for various applications.
• The validated method offers a valuable tool for materials design and optimization in flexible electronics and wearable devices.