石墨烯是一种碳原子以单一的sp2结构排列而成的单原子层物质，同时p轨道上垂直于石墨烯片层表面的电子形成离域大π键，电子可以在石墨烯表面上自由运动。与石墨烯拥有类似结构的氮化硼、二硫化钼等二位纳米材料统称为石墨烯类似物，石墨烯及其类似普遍拥有很高的比表面积、良好的力学、电学、热学等性能，非常适合作为聚合物复合材料中的增强填料来使用。石墨烯及其类似物与聚合物基体材料之间的相互作用主要包括氢键、共轭作用、分子间力、配位键和成核结晶作用。其中配位作用是通过中心离子提供空轨道，配位原子提供孤对电子形成配位键的方式来在石墨烯与基体聚合物之间构筑相互作用的。本文深入研究了通过引入金离子配位键在石墨烯及其类似物与聚合物复合材料之间构筑强相互作用，从而提升复合材料力学、电学、热学等性能的方法。本文首先制备了含有铜离子配位作用的Cu(II)-GO/PEO，Cu(II)-GO/PVA复合材料，在GO/PEO、GO/PVA复合材料体系中添加铜离子引入配位键，在一定温度下促成配位键的形成之后制备复合材料薄膜。使用紫外光谱和红外光谱等方法验证配位键是否成功作用与基体聚合物和石墨烯填料之上，用原子力显微镜观察了原料GO与包覆了聚合物的GO的形貌，对材料进行力学、热学测试的结果显示，在金属离子配位键引入之后，材料的力学和热学性能均有显著提升。在研究了聚合物为基体的复合材料的性能之后，本文研究了通过配位作用将两种二位纳米材料的性能结合到一起的方法，制备了以还原石墨烯(rGO)和六方氮化硼(h-BN)为基体，加入PEO作为桥接剂，加入二价钙离子引入配位作用的复合材料。金属离子的配位作用成功在rGO、h-BN和PEO之间构筑了界面相互作用，得到了力学、电导率、热导率三项性能俱佳的纳米复合材料。在对溶液法制备的复合材料进行了研究之后，本文还研究了熔融法制备GO/PMMA复合材料的过程中引入金属离子配位键的情况。发现三价金属离子的引入可以大幅提升材料的力学性能和热稳定性。本文还采用了母料法和直接熔融法两种方法制备了复合材料并测试它们的性能，发现分散性更好的母料法得到的样品性能更佳。
Graphene is the most famous representative of 2D nanomaterials. It has a unique structure, which is composed of one-atom-thick sp2-hybridized carbon network with large delocalized pi-bond on the molecular layer. Hexagonal boron nitride, molybdenum disulfide, tungsten disulfide etc. are called grapheme analogues, for they have similar 2D nanostructures with grapheme. As the result of their unique structures, graphene and its analogues have large specific surface area, good mechanical property, electrical property or thermal property. So graphene and its analogues are usually added into polymers to form nanocomposites to improve varieties of properties. In these composites, the interaction between filler and matrix contains hydrogen bonding, π-π bonding, Van der waal’s force and coordination bonding. In this paper, we focused on coordination bonding in garphene(or its analogues)/polymer nanocomposite, trying to introduce metal ions into these systems to increase their mechanical, electrical or thermal properties.Firstly, copper ion coordinated GO/PEO and GO/PVA composite were prepared by aqueous solution method. UV-Vis and FT-IR spectra were used to confirm the formation of coordination bonding between filler (GO) and matrix (PEO or PVA). Atomic force microscopy images of GO and Cu(II)-GO/PEO, Cu(II)-GO/PVA showed the nanostructure of GO sheets. The mechanical properties and thermal stabilities of Cu(II)-GO/PEO and Cu(II)-GO/PVA are significantly higher than GO/PEO and GO/PVA respectively. This result showed that the introduction of metal ion coordination improved the interaction between GO filler and polymer matrix.Then, nanomaterial-matrix composite Ca(II)-rGO/BN/PEO was prepared. In this chapter, reduced grapheme oxide and hexagonal boron nitride were bonded with calcium coordination. Poly (ethylene oxide) was added as reinforcement to bridge the two nanomaterials. After calcium ions were added, the mechanical, electrical and thermal properties were all improved. The sample Ca(II)-rG4B6P4 showed good performance in all these three aspects.Melt method is also a good way to synthesize graphene/polymer nanocomposites. Iron ions and copper ions coordinated GO/PMMA composite were prepared with melt method. After coordination, the mechanical properties were improved significantly with both metal ions. Msterbatch melt method and direct melt method were compared in this study. The result showed that the masterbatch melt method was obviously better than the other one, because it help GO sheets disperse better in PMMA matrix.
