高导热石墨烯纤维的制备及性能研究

Fibers with high thermal conductivity play significant roles in functional composite materials, intelligent garment and military equipment. As an emerging carbonaceous fiber, graphene fiber (GF) is hoped to inherit the exceptional thermal conductivity of single graphene sheet and become a promising thermally conductive material. Targeting on the controllable preparation of highly thermally conductive GF and its structure-property relationship, we will systematically study the preparation of less-defective graphene oxide, wet-spinning assembly, post-treatment, and thermally conductive performance of the GFs. The evolution of the multilevel structural defects in the overall process will be characterized in detail. We will also study the effect of the basic assembly micro-structure on the thermally conductive properties of the GF and explore the effective approaches to improve the thermal conductivity. This project will realize the successful preparation of highly thermally conductive GFs and establish the fundamental relationship between structure and performance, which will help to upgrade the combined performance of the GFs. Additionally, this study will also contribute to further development of the graphene materials with macroscopically ordered structure.

高导热纤维在功能复合材料、智能服饰、军用装备等领域有重要的应用价值。作为一种新型碳质纤维，石墨烯纤维有望继承单片石墨烯优异的导热特性，成为有发展前景的导热材料。本项目针对高导热石墨烯纤维的可控制备及结构性能关系，拟从低缺陷氧化石墨烯可控制备及结构优化、氧化石墨烯纤维的可控制备、石墨烯纤维低缺陷化处理、纤维微纳尺度缺陷结构调控以及导热性能精确测试等方面开展系统深入的研究。逐步阐明原料制备、湿法组装、液固相变以及低缺陷化处理过程中多级多尺度结构缺陷演变规律，剖析结构缺陷对纤维导热性能的影响，理解石墨烯纤维导热特性的微观结构机制，探索提高石墨烯纤维导热率的方法。本项目将实现高导热石墨烯纤维的可控制备，建立深入的结构性能关系认识，为提升石墨烯纤维的综合性能提供理论依据，同时有助于推动其他石墨烯宏观有序材料的发展。

石墨烯纤维是由石墨烯基元沿轴向有序堆积排列而成的连续组装材料，具有高力学性能和功能特性。本项目重点研究石墨烯纤维的导热性能及结构影响因素。从低缺陷氧化石墨烯可控制备及结构优化、氧化石墨烯纤维的可控制备、石墨烯纤维低缺陷化处理、纤维微纳尺度的结构调控以及导热性能精确测试等方面开展系统深入的研究。阐明了氧化石墨烯原料制备、湿法组装、液固相变以及低缺陷化处理过程中多级多尺度缺陷结构演变规律，建立了纤维取向度、晶区尺寸与石墨烯纤维导热性能的关系，石墨烯纤维导热率达1480 W/mK，导电率为1.2 MS/m，力学强度达到了3.4 GPa，模量341 GPa。通过本项目，建立了高导热石墨烯纤维的制备方法系统，为后续工程化制备石墨烯纤维丝束提供了宝贵的研究经验；加深了对石墨烯纤维结构和性能构效关系的认识，为进一步开展石墨烯纤维结构设计和优化石墨烯纤维制备工艺指明了方向。在完成研究计划的基础上，还将高导热石墨烯纤维的研究经验和研究方法拓展到石墨烯纳米纤维、高导热石墨烯薄膜连续化制备、溶致塑化发泡法制备石墨烯气凝胶等，推动石墨烯宏观组装材料的发展。.项目执行期间，在Science Advances、Small、Carbon等期刊发表基金标注论文10篇，授权中国发明专利3项，做国内学术会议邀请报告3次。积极对接国家需求，获得2项军科委项目资助，推进石墨烯研究成果在国防领域的转化和应用。