Abstract Graphene oxide (GO) was functionalized to prepare GO/polyurethane (PU) composites with improved thermal properties. To improve the dispersion of GO in PU, GO is modified with the ionic liquid of 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl) imide ([BMIm]Tf2N) to obtain the functionalized GO (IL-GO), which could form homogeneous dispersions in N,N-dimethyl formamide (DMF) solvent. The structure and morphology characterizations of GO and IL-GO showed that the ionic liquid had been successfully grafted on the surface of GO through non-covalent bonding. The interlayer distance of the GO also increased to 1.01 nm after modification. Following the solution mixing method, the IL-GO/PU composites were prepared. It is found that IL-GO could provide a good compatibility with the PU. When the contents of IL-GO range from 0 to 2 wt.%, the thermal stabilities of the IL-GO/PU composites are gradually enhanced. At the IL-GO content value of 2 wt.%, the glass transition temperature was increased by 56.4 °C, and the thermal decomposition temperature on 10% weight loss was approximately 45 °C higher than that of the pure PU.

中文翻译：

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改性氧化石墨烯/聚氨酯复合材料的制备及性能

摘要 氧化石墨烯 (GO) 被功能化以制备具有改进热性能的 GO/聚氨酯 (PU) 复合材料。为了提高 GO 在 PU 中的分散性，用 1-丁基-3-甲基咪唑鎓双（三氟甲基磺酰基）亚胺（[BMIm]Tf2N）的离子液体对 GO 进行改性，得到功能化的 GO（IL-GO），它可以形成均质的N,N-二甲基甲酰胺 (DMF) 溶剂中的分散体。GO和IL-GO的结构和形貌表征表明，离子液体已通过非共价键成功接枝在GO表面。修饰后GO的层间距也增加到1.01 nm。按照溶液混合方法，制备了 IL-GO/PU 复合材料。发现IL-GO可以提供与PU的良好相容性。当 IL-GO 的含量范围为 0 至 2 wt.% 时，IL-GO/PU 复合材料的热稳定性逐渐增强。在 IL-GO 含量值为 2 wt.% 时，玻璃化转变温度提高了 56.4 °C，10% 失重时的热分解温度比纯 PU 高约 45 °C。