Guo Haichang, Zhao Haoyuan, Niu Hongyu, Ren Yanjuan, Fang Haoming, Fang Xingxing, Lv Ruicong, Maqbool Muhammad, Bai Shulin
School of Materials Science and Engineering, CAPT/HEDPS/LTCS, Key Laboratory of Polymer Chemistry and Physics of Ministry of Education, Peking University, Beijing 100871, China.
National Synchrotron Radiation Laboratory, Anhui Provincial Engineering Laboratory of Advanced Functional Polymer Film, CAS Key Laboratory of Soft Matter Chemistry, University of Science and Technology of China, Hefei 230026, China.
ACS Nano. 2021 Apr 27;15(4):6917-6928. doi: 10.1021/acsnano.0c10768. Epub 2021 Apr 15.
Efficient thermal transportation in a preferred direction is highly favorable for thermal management issues. The combination of 3D printing and two-dimensional (2D) materials such as graphene, BN, and so on enables infinite possibilities for hierarchically aligned structure programming. In this work, we report the formation of the asymmetrically aligned structure of graphene filled thermoplastic polyurethane (TPU) composites during 3D printing process. The as-printed vertically aligned structure demonstrates a through-plane thermal conductivity (TC) up to 12 W m K at 45 wt % graphene content, which is ∼8 times of that of a horizontally printed structure and surpasses many of the traditional particle reinforced polymer composites. The superior TC is mainly attributed to the anisotropic structure design that benefited from the preferable degree of orientation of graphene and the multiscale dense structure realized by finely controlling the printing parameters. Finite element method (FEM) confirms the essential impact of anisotropic TC design for highly thermal conductive composites. This study provides an effective way to develop 3D printed graphene-based polymer composites for scalable thermal-related applications such as battery thermal management, electric packaging, and so on.
在热管理问题中，沿优选方向进行高效的热传输非常有利。3D打印与二维（2D）材料（如石墨烯、氮化硼等）的结合为分层排列结构的设计提供了无限可能。在这项工作中，我们报道了在3D打印过程中形成的石墨烯填充热塑性聚氨酯（TPU）复合材料的不对称排列结构。在石墨烯含量为45 wt%时，打印出的垂直排列结构的面内热导率（TC）高达12 W m⁻¹ K⁻¹，约为水平打印结构的8倍，超过了许多传统颗粒增强聚合物复合材料。优异的热导率主要归因于各向异性结构设计，这得益于石墨烯的优选取向程度以及通过精细控制打印参数实现的多尺度致密结构。有限元方法（FEM）证实了各向异性热导率设计对高导热复合材料的重要影响。本研究为开发用于可扩展热相关应用（如电池热管理、电气封装等）的3D打印石墨烯基聚合物复合材料提供了一种有效方法。
