Highly Thermally Conductive Polyimide Composites via Constructing 3D Networks.

Area of Science:

• Materials Science
• Polymer Science
• Nanotechnology

Background:

• High thermal conductivity is crucial for electronic packaging to manage heat.
• Current methods for producing thermally conductive polymer composites often lack efficiency or high performance.
• Polyimide (PI) composites are desirable for their thermal stability, but often have low thermal conductivity.

Purpose of the Study:

• To develop an easy and highly efficient method for fabricating polyimide/boron nitride (PI/BN) composites with enhanced thermal conductivity.
• To investigate the formation of 3D thermally conductive networks within the PI matrix.
• To achieve superior thermal conductivity performance for electronic packaging applications.

Main Methods:

• Coating boron nitride (BN) platelets onto polyimide (PI) granules using a PI adhesive.
• Fabricating PI/BN composites through hot pressing to create well-arranged BN networks.
• Characterizing the thermal conductivity of the resulting composites.

Main Results:

• Achieved high thermal conductivity of 4.47 W mK⁻¹ in PI/BN composites with only 20 vol% BN loading.
• Demonstrated a 2099% enhancement in thermal conductivity compared to pure PI.
• Observed the formation of tightly connected and well-arranged 3D BN networks within the PI matrix.

Conclusions:

• The developed method provides an effective route to significantly enhance the thermal conductivity of polymer composites.
• The formation of physical connections (aggregates) of thermally conductive fillers is key to promoting composite thermal conductivity.
• These PI/BN composites offer a promising solution for thermal management in electronic packaging.