The effect of the polymeric cross-link density on the thermal conductivity of an oxidized graphene (OG)-filled epoxy nanocomposite was investigated by two different fabrication methods, namely a conventional OG mixing (OG conventional ) and a diamine–colloidized OG (OG colloidized ) method. Epoxy composites with 3 wt% OG were prepared via the diamine–OG fabrication method to produce an epoxy nanocomposite with a higher cross-link density than that of an epoxy composite with also 3 wt% of OG prepared via the conventional fabrication method. The cross-link densities of the epoxy nanocomposites were calculated by means of a solvent swelling test. The epoxy/OG colloidized nanocomposite showed a higher cross-link density and higher thermal conductivity than the epoxy/OG conventional nanocomposite with the same filler concentration. It was observed that for the epoxy/OG colloidized nanocomposite, where an amide network was relatively formed between the carboxylic and amine groups, a high cross-link density enhanced the thermal conductivity by means of the transport of phonons. Furthermore, high dispersion of OG gives high dielectric constant to epoxy/OG colloidized even having the same amount of graphene loading.

中文翻译：

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使用胶体聚合方法提高石墨烯填充环氧树脂纳米复合材料的导热系数和介电常数

通过两种不同的制备方法研究了聚合物交联密度对氧化石墨烯 (OG) 填充环氧树脂纳米复合材料的热导率的影响，即传统的 OG 混合（OG 常规）和二胺胶体化的 OG（OG 胶体化）。 ） 方法。通过二胺-OG 制备方法制备了含 3 wt% OG 的环氧复合材料，以生产出具有比通过常规制备方法制备的同样含 3 wt% OG 的环氧复合材料更高的交联密度的环氧纳米复合材料。环氧纳米复合材料的交联密度通过溶剂溶胀试验计算。与具有相同填料浓度的环氧树脂/OG 常规纳米复合材料相比，环氧树脂/OG 胶体化纳米复合材料表现出更高的交联密度和更高的热导率。观察到，对于环氧树脂/OG 胶体化纳米复合材料，在羧基和胺基之间相对形成酰胺网络，高交联密度通过声子的传输增强了热导率。此外，即使具有相同量的石墨烯负载量，OG 的高分散性也为胶体化的环氧树脂/OG 提供了高介电常数。 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .