Polyurethane packed graphene-coated spider silk by dip-casting for a highly stretchable strain sensor

Area of Science:

• Materials Science
• Biomaterials Engineering
• Wearable Electronics

Background:

• Naturally occurring materials are increasingly explored for advanced wearable electronics.
• Spider silk offers exceptional mechanical strength and unique physical properties suitable for sensor fabrication.

Purpose of the Study:

• To develop a highly stretchable strain sensor using graphene-coated spider silk.
• To leverage the self-healing and protective properties of polyurethane for enhanced sensor performance and longevity.

Main Methods:

• Fabrication of graphene-coated spider silk via dip-casting.
• Encapsulation of the coated silk with polyurethane for packaging.
• Characterization using FE-SEM and EDS elemental mapping.
• Testing sensor performance under various strain levels and on human body parts.

Main Results:

• The sensor exhibited remarkable mechanical strength, high sensitivity, and excellent recovery properties due to polyurethane's self-healing ability.
• The device maintained performance up to 40% stretchability, with polyurethane protecting against environmental factors.
• Successful monitoring of pulse rate, joint angles, and posture when attached to the human body.

Conclusions:

• This study demonstrates the potential of using naturally occurring spider silk for creating robust and high-performance wearable strain sensors.
• The developed sensor technology paves the way for future advancements in wearable electronics and health monitoring applications.