西北工业大学顾军渭团队报道了热传导液晶聚酰亚胺复合膜内功能化碳纳米管的电场诱导取向。相关研究成果发表在2023年8月7日出版的《德国应用化学》。

正性液晶，4’-庚基-4-联苯腈（7CB），用于功能化碳纳米管（LC-CNT），可以在交变电场下在液晶聚酰亚胺（LC-PI）基体中排列，以制备导热的LC-CNT/LC-PI复合膜。通过LC-CNT在LC-PI基质内的定向排列，实现了在具有低量LC-CNT的导热LC-CNT/LC-PI复合膜中该校热传导途径的建立。

当LC-CNT的质量分数为15wt%时，LC-CNT/LC-PI复合膜的面内导热系数（λ⊥），也分别比CNT/LC-PI复合膜高28.8%和5.8%。同时，热传导性LC-CNT/LC-PI复合膜也具有优异的机械性能和耐热性能。杨氏模量和耐热指数分别为2.3GPa和297.7oC，高于相同CNT量下的固有导热LC-PI薄膜和导热CNT/LC-PI复合薄膜。

附：英文原文

Title: Electric-Field-Induced Alignment of Functionalized Carbon Nanotubes Inside Thermally Conductive Liquid Crystalline Polyimide Composite Films

Author: Kunpeng Ruan, Xuetao Shi, Yali Zhang, Yongqiang Guo, Xiao Zhong, Junwei Gu

Issue&Volume: 2023-08-07

Abstract: The 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 297.7oC, 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.

DOI: 10.1002/anie.202309010

Source: https://onlinelibrary.wiley.com/doi/10.1002/anie.202309010