Harmonizing Elastic Modulus and Dielectric Constant of Elastomers for Improved Pressure Sensing Performance

Area of Science:

• Materials Science
• Polymer Science
• Sensor Technology

Background:

• Microstructure design in capacitive pressure sensors can reduce reliability and require complex manufacturing.
• Balancing intrinsic properties of dielectric materials is key to overcoming these limitations.

Purpose of the Study:

• To develop a novel liquid metal (LM) hybrid elastomer for flexible pressure sensors.
• To improve sensor sensitivity and reliability by modifying material properties.

Main Methods:

• Synthesized a chain-extension-free polyurethane (PU) and LM hybrid elastomer.
• Investigated the synergistic effects of extender-free synthesis and LM doping on material properties.
• Fabricated flexible pressure sensors using the developed hybrid elastomer.

Main Results:

• Reduced elastic modulus from 7.6 ± 0.2 to 2.1 ± 0.3 MPa.
• Enhanced dielectric constant from 5.12 to 8.17 @1 kHz.
• Demonstrated reprocessability, recyclability, and photothermal conversion properties.
• Achieved high-precision speech recognition (seven words) using a convolutional neural network (CNN).

Conclusions:

• The developed LM hybrid elastomer offers a promising approach for creating sensitive, reliable, and recyclable flexible pressure sensors.
• This material is suitable for detecting physiological movements and advanced human-machine interfaces.
• The study provides a new strategy for designing intelligent, wearable pressure sensing devices.