Abstract

AbstractThe positive liquid crystals, 4′‐heptyl‐4‐biphenylcarbonitrile (7CB), are used to functionalize carbon nanotubes (LC‐CNT), which can be aligned in the liquid crystalline polyimide (LC‐PI) matrix under an alternating electric field to fabricate the thermally conductive LC‐CNT/LC‐PI composite films. The efficient establishment of thermal conduction pathways in thermally conductive LC‐CNT/LC‐PI composite films with a low amount of LC‐CNT is achieved through the oriented alignment of LC‐CNT within the LC‐PI matrix. When the mass fraction of LC‐CNT is 15 wt %, the in‐plane thermal conductivity coefficient (λ∥) and the through‐plane thermal conductivity coefficient (λ⊥) of the LC‐CNT/LC‐PI composite films reach 4.02 W/(m ⋅ K) and 0.55 W/(m⋅K), which are 90.5 % and 71.9 % higher than those of the intrinsically thermally conductive LC‐PI films respectively, also 28.8 % and 5.8 % higher than those of the CNT/LC‐PI composite films respectively. Meanwhile, the thermally conductive LC‐CNT/LC‐PI composite films also possess excellent mechanical and heat resistance properties. The Young's modulus and the heat resistance index are 2.3 GPa and 297.7 °C, respectively, which are higher than the intrinsically thermally conductive LC‐PI films and the thermally conductive CNT/LC‐PI composite films under the same amount of CNT.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.