Boron Nitride/Polyurethane Composites with Good Thermal Conductivity and Flexibility

Area of Science:

• Materials Science
• Polymer Chemistry
• Nanotechnology

Background:

• Thermal insulating composites are crucial for electronics but face limitations in thermal conductivity and flexibility.
• Hexagonal boron nitride (BN) offers excellent thermal conductivity and electrical insulation, making it a promising filler for polymer composites.

Purpose of the Study:

• To fabricate BN/polyurethane (PU) composites with improved thermal performance and flexibility.
• To investigate the thermal conductivity, electrical resistivity, and mechanical properties of the developed composites.

Main Methods:

• Utilized an improved nonsolvent-induced phase separation method with binary solvents.
• Incorporated hexagonal boron nitride (BN) into a polyurethane (PU) matrix.
• Characterized the thermal, electrical, and mechanical properties of the BN/PU composites.

Main Results:

• BN/PU composites exhibited significantly enhanced thermal conductivity (0.653 W/(m·K)) and volume resistivity (23.9 × 10^12 Ω·cm) compared to pure PU.
• The composites demonstrated excellent flexibility, maintaining integrity after 1000 bending cycles.
• Achieved high stress (7.52 ± 0.87 MPa) and strain (707.34 ± 38.34%) for the BN60/PU composite.

Conclusions:

• The developed BN/PU composites offer a practical solution for efficient thermal management in flexible electronic applications.
• The improved fabrication method yields materials with superior thermal and mechanical reliability.
• These findings pave the way for advanced flexible materials in demanding electronic environments.