Thermally conductive, self-healing, and elastic Polyimide@Vertically aligned carbon nanotubes composite as smart thermal interface material

By Huitao Yu, Yiyu Feng, Can Chen, Zhixing Zhang, Yu Cai, Mengmeng Qin, W. Feng. Carbon, 2021

150 citations recorded by the source corpus.

Abstract Smart thermal interface materials must exhibit self-healability and high thermal conductivity (k) and elastic deformation as they can experience repeated compression and undergo sudden damage. However, it remains challenging to ensure high phonon mobility/efficient phonon transfer, self-healing, and good elasticity by optimizing its molecular orientation or cross-links. Herein, a self-healing and elastic polyimide copolymer (EMPI) cross-linked by flexible and rigid segments is uniformly filled into the gaps of a forest of vertically aligned carbon nanotubes (VACNTs). The EMPI@VACNTs composite exhibits a high k value at 10.83 ± 0.22 W m-1 K-1, low interfacial thermal resistance at 6.83 ± 0.15 K mm2 W-1, high elastic compressive deformation (30% at 2.5 MPa), and strong surface adhesion (0.3 MPa). Further, it could recover 90.8% of its elastic modulus and 92% of its thermal resistance after self-healing at 80°C for 80 h. An EMPI@VACNTs-Cu device exhibits efficient heat conduction not only by recovering after gradient compressive strains of up to 30% but also by self-healing its damage or reforming the interface with Cu. Thus, the thermally conductive, self-healing, and elastic EMPI@VACNTs composite opens new avenues for smart thermal management in various high-power/intelligent devices.

Subfields: Biomedical Engineering, Materials Chemistry, Polymers and Plastics

View Paper: https://www.semanticscholar.org/paper/b2cbf72b37f287f0e6e4d76f2f0d34be1f44782d