高品质石墨烯的绿色宏量制备及其在聚合物基复合材料中的有效利用

Large-scale preparation of high-quality graphene through an economical way is a critical prerequisite to realize the multifunctional polymer/graphene composites. To address such issue, a so-called plant polyphenol-assisted liquid-phase exfoliation method, which is a low-cost, high-yield and green method of graphene production, has been developed here for producing graphene directly from natural graphite. Plant polyphenol can not only interact strongly with the basal plane of graphene through π-stacking, but also pay the way for the “interface molecular design” of specific polymer system through phenolic hydroxyl groups and their ortho-para active hydrogens. During the implementation of such a proposal, the effects of various parameters will be systematically studied in order to reveal the regular rule and thus develop a “plant polyphenol-assisted liquid-phase exfoliation method” for producing high-quality graphene in large quantities. Also, both the molecular mechanism of plant polyphenol or its derivatives-graphene and plant polyphenol or its derivatives-matrix interactions will be found out. Meanwhile, the importance of “noncovalent functionalization of graphene” and “interface molecular design”, which is guided by specific application of graphene, in preparing polymer/graphene composites will also be fully understood so that a new strategy for preparing and applying graphene can be inaugurated.

低成本、宏量制备高品质石墨烯是实现石墨烯在多功能聚合物复合材料领域应用的前提和基础。为此，本项目发展了一种以植物多酚作为分散助剂，从天然石墨中直接液相剥离石墨烯的方法，具有成本低、产率高和绿色环保等优点。植物多酚不仅能够通过π-π作用吸附到石墨烯表面，而且其结构中的酚羟基及其邻对位氢为实现具体复合体系的界面分子设计提供了数量众多的活性反应位。项目实施中，一方面具体研究植物多酚种类和制备工艺参数对石墨烯品质、分散液浓度、分散液稳定性的影响，揭示规律，优化实施方案，以宏量提供高品质石墨烯；一方面明晰植物多酚或其衍生物与石墨烯、基体树脂相互作用的分子机理，深化理解和认识“石墨烯物理修饰”和“界面分子设计”概念在聚合物/石墨烯复合材料制备过程中的重要性，为石墨烯的制备与应用提供一种新思路。

石墨烯具有优异的力学、导电、导热和气体阻隔等性能，在高性能和多功能聚合物复合材料领域具有重要的应用。然而，商品化石墨烯的高成本（>1000元/千克）、低性能（电导率一般<100 S·cm-1）以及难分散等诸多问题，严重制约了石墨烯在复合材料领域的应用。本项目以植物多酚为分散剥离助剂，实现了低成本（~400元/千克）、高品质（电导率~500 S·cm-1）石墨烯的高效水相剥离，并基于所制备的植物多酚修饰石墨烯成功地开发出了兼具优异力学性能（高拉伸强度、高撕裂强度、低磨耗、低压缩永久变形、低压缩生热等）和功能性（阻燃等级V-0级和电磁干扰屏蔽效能> 40 dB）的橡胶复合材料，以及可涂刷或喷涂到橡胶或发泡聚苯乙烯表面实现其V-0级阻燃的石墨烯协效阻燃弹性体/树脂涂层。