Highly thermally conductive, ductile biomimetic boron nitride/aramid nanofiber composite film
Highly thermally conductive, ductile biomimetic boron nitride/aramid nanofiber composite film
复制标题
DOI：
10.1016/j.compscitech.2020.108021
复制
发表时间：
2020-03-22
影响因子：
9.1
通讯作者：
Wang, Jianfeng
中科院分区：
文献类型：
--
作者：
Xiao, Guang;Di, Jiangtao;Wang, Jianfeng
将大量氮化硼片与少量聚合物相结合来制造用于柔性电子设备热管理的延展性导热复合材料是一项挑战。在此，我们模仿软体动物珍珠层的分层结构来设计高负载氮化硼复合膜。采用溶胶-凝胶-薄膜转化方法制备了氮化硼/芳纶纳米纤维复合薄膜，并呈现出珍珠层状的分层层状复合结构。高强度芳纶纳米纤维形成三维骨架作为基体，其中含有 40-70 wt% 的取向 BN 片晶。由于芳纶纳米纤维在三维骨架中的高互连性，复合薄膜具有很大的延展性，高达18.3-49.4%。同时，由于高负载氮化硼片形成渗透的定向导热路径，复合薄膜具有高导热率（47.4-122.5 W m(-1) K-1）。此外，出色的延展性和导热性与高体积电阻率（10(14)-10(16) Omega cm）和热分解温度（515摄氏度）相结合，使得结构化氮化硼/芳纶纳米纤维复合薄膜有望作为冷却电子元件的柔性基板。
Combining a large volume of boron nitride platelets with a little polymer to fabricate ductile, thermally conductive composite materials for the thermal management of flexible electronic devices is a challenge. Herein, we imitate the hierarchical layered architecture of mollusk nacre to design high-loading boron nitride composite film. Boron nitride/aramid nanofiber composite films are prepared by a sol-gel-film transformation approach and show nacre-like hierarchical layered composite structure. High-strength aramid nanofibers form a three-dimensional framework as matrix, which hosts 40-70 wt% oriented BN platelets. Thanks to the high inter-connectivity of aramid nanofiber in the three-dimensional framework, the composite films have large ductility, up to 18.3-49.4%. Meanwhile, the composite films have high thermal conductivity (47.4-122.5 W m(-1) K-1) because high-loading boron nitride platelets form a percolative, oriented heat conduction path. Moreover, the outstanding ductility and thermal conductivity are integrated with high volume resistivity (10(14)-10(16) Omega cm) and thermal decomposition temperature (515 degrees C), enabling the structured boron nitride/aramid nanofiber composite films to be promising as flexible substrate for cooling electronic components.