Abstract Graphene oxide (GO) was synthesized from expanded graphite with particle size of 130 μm (GO130) and 1200 μm (GO1200) and characterized. GO130 was oxidized to a higher degree and contained larger concentration of C O bonds. After the synthesis, the GO was kept in a form of viscous slurry in methanol to prevent formation of graphite oxide. The slurry was mixed with a hardener and methanol was evaporated. The nanocomposites with GO content from 0.25 to 1.0 wt% were prepared by mixing the epoxy resin, hardener and hardener/GO mixture and cured. The particles were homogeneously distributed within the polymer matrix as observed by SEM on the plasma etched samples. The glass transition temperature increased from 81 °C to up to 90 °C. The Young’s modulus increased by 35% and 30% with the addition of GO130 and GO1200, respectively, while the tensile strength increased for 10% only when GO1200 had been added. The optimum concentration of GO in the nanocomposite is from 0.25 to 0.50 wt%.

中文翻译：

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氧化石墨烯一步表面改性及其粒径对氧化石墨烯/环氧树脂纳米复合材料性能的影响

摘要 以膨胀石墨为原料合成氧化石墨烯 (GO)，粒径分别为 130 μm (GO130) 和 1200 μm (GO1200)，并对其进行表征。GO130 被氧化到更高的程度并包含更大浓度的 CO 键。合成后，将 GO 保持在甲醇中的粘性浆液中，以防止形成氧化石墨。将浆液与硬化剂混​​合并蒸发甲醇。通过混合环氧树脂、硬化剂和硬化剂/GO混合物并固化，制备GO含量为0.25至1.0wt%的纳米复合材料。如通过 SEM 在等离子体蚀刻样品上观察到的，颗粒均匀分布在聚合物基质中。玻璃化转变温度从 81 °C 增加到高达 90 °C。添加 GO130 和 GO1200 后，杨氏模量分别增加了 35% 和 30%，而加入GO1200后抗拉强度增加了10%。纳米复合材料中 GO 的最佳浓度为 0.25 至 0.50 wt%。