热稳定性增强的三聚氰胺功能化石墨烯基纳米杂化材料

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摘要石墨烯，源于其优异的物化性能，自 2004 年被机械剥离成功制备以来，一直被认为是优质的纳米填料。在提高聚合物的机械，电学以及热学性能等方面表现出了优异的性能，受到了来自各国学者的广泛关注。但石墨烯表面不含任何功能基团，难溶于任何溶剂，且片层间较强的范德华力使其极易团聚，严重阻碍了在化工领域的应用。因此，如何对石墨烯进行有效功能化，同时实现其溶液分散性及热性能已成为制约该领域的重要研究课题。68559

石墨烯的功能化方法很多，主要分为共价功能化与非共价功能化。本论文以改良后的 Hummers 方法制备的氧化石墨（GO）为前驱体，利用 2 种有机合成技术构筑了两类三聚氰胺（Melamine，MA）功能化的石墨烯杂化材料。主要分为：

（1）利用二氯亚砜对 GO 羧基进行活化，再将 MA 偶联于其 GO 的边缘，考察了不同温度改性条件下，得到的一系列杂化材料 GO-MA 的分散性能和热稳定性能；

（2）在无任何有毒偶联剂存在条件下，利用有机合成中亲核加成经典反应及静电自组装手段，将 MA 直接修饰于 GO 的表面，也得到一系列杂化材料 MA-mGO，并考察了其分散性能和热稳定性能。

以上得到的产物均经过 FT-IR、XRD、Raman、TG、SEM、TEM 等检测手段进行分析和确认。结果表明：两大系列 MA 功能化的杂化材料均成功制备，且其热稳定性相对于 GO 有显著提高。并且在不同的反应温度下的复合物其热稳定性的提高有所不同，先随着反应温度的升高，杂化材料的热稳定性提高。但当温度达到一定值时，热稳定性反而下降，呈现正态分布，存在极大优化值。并且,GO-MA 和 MA-mGO 的分散性明显优于 GO，可以进行溶液处理，简化了复合材料制备中的繁杂步骤。本文所取得的成果将为阻燃材料等领域提供一定的数据支撑和实践经验。

毕业论文关键词：氧化石墨三聚氰胺杂化材料热稳定性

Title Enhanced Thermal Stability of Melamine Functionalized Graphene-base Nanohybrid materials

Abstract

Graphene has been considered excellent nanofillers due to its fantastic properties since it was discovered using micromechanical cleavage in 2004. Graphene have been focused widely by researchers from all over the word, due to it excellent properties in enhancing electrical, mechanical and thermal properties of polymer. But graphene dose not dissolve in any organic solvents due to its surface not containing any functional groups and agglomerate easily due to strong Van der Waals' force between graphene sheets, which hinder from its applications in chemical industry. Therefore, how to functionalize graphene effectively and achieve the dispersibility in organic solvents and thermal properties simultaneously has been an importment research project which confining this field.

There are many functionalized methods of graphene, and mainly include covalent and noncovalent modification methods. In this thesis,graphite oxide(GO) was prepared by modified Hummers method, and utilized it as precursor to fabricate two graphene nanohybirds which were functionalized with melamine(MA) by using two kinds of organic synthesis technologies. The expriments mainly pided into below parts: (1)utilizing the dichlorosulfoxide to activate carboxyl groups on GO, and coupling MA in the edge of the GO, and then investigating the dispersibility and thermalstability of a series of nanohybirds named GO-MA at different modified temperatures; (2)modifying MA on the surface of GO directly utilizing classic nucleophilic addition reactions in organic synthesis and electrostatic self-assembly method without any toxic coupling reagents. We obtained a series of nanohybirds named MA-mGO and investigated their