Electromechanical Properties of 3D-Printed Stretchable Carbon Fiber Composites

Area of Science:

• Materials Science and Engineering
• Additive Manufacturing
• Polymer Science

Background:

• Fused filament fabrication (FFF) commonly uses carbon fillers to enhance 3D-printed materials.
• Integrating fillers into stretchable matrices presents challenges in maintaining quality and durability.
• Carbon fiber cloth (CFC) offers a potential solution for reinforcing stretchable thermoplastic polyurethane (TPU).

Purpose of the Study:

• To investigate the integration of carbon fiber cloth (CFC) into stretchable thermoplastic polyurethane (TPU) matrices.
• To evaluate the electromechanical properties and durability of CFC-reinforced TPU composites for 3D-printed electronics.
• To assess the potential of these composite structures as sensors.

Main Methods:

• Preparation of four series of CFC-reinforced TPU samples with varying CFC layer thicknesses (53–159 µm).
• Mechanical testing including single pull-up and 10,000-cycle cyclic tensile tests.
• Electrical property assessment and digital image correlation (DIC) analysis.

Main Results:

• Embedded CFC layers in TPU matrices enable the creation of stretchable 3D-printed electronic structures.
• Thin CFC layers (53 µm) maintained electrical properties under 50% cyclic deformation.
• Thicker CFC layers (>150 µm) achieved the lowest resistance (5 Ω/10 mm), while 106-µm layers offered balanced electromechanical performance with minimal resistance change (0.5%) after cyclic testing.

Conclusions:

• Carbon fiber cloth is a viable reinforcement for creating durable and conductive stretchable 3D-printed materials.
• The electromechanical properties can be tuned by adjusting CFC layer thickness for specific applications.
• The developed composite structures show promise for use in stretchable sensors and electronic components.