Abstract Supercritical carbon dioxide (scCO2) was considered as an environmental friendly medium for grafting the surface of silica nanoparticles with a series of reactive imidazolium-based ionic liquids (IL), denoted as IL-silanes. The effects of the reaction conditions on the resulting IL-grafted layers on the silica surface were characterized from thermogravimetric (TGA) and transmission electronic microscopy (TEM) analyses. The IL-grafted nanoparticles were introduced into poly(methyl methacrylate) (PMMA) via melt mixing in order to design nanocomposites and to demonstrate the ability of IL-grafted nanoparticles to be dispersed into a polymer medium. The role of the IL-grafted surfaces on the morphology of PMMA-based nanocomposites was evidenced by TEM and small angle neutron scattering (SANS). It was demonstrated that longer the alkyl chain length of the IL-silane, better the state of dispersion of nanoparticles within PMMA. In addition, better thermal stabilities and mechanical performances, as well as new surface properties were observed for the designed PMMA-based nanocomposites.

中文翻译：

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在超临界 CO2 条件下接枝离子液体的离子 PMMA/纳米二氧化硅界面

摘要 超临界二氧化碳 (scCO2) 被认为是一种环境友好的介质，用于接枝二氧化硅纳米粒子的表面与一系列活性咪唑基离子液体 (IL)，表示为 IL-硅烷。通过热重 (TGA) 和透射电子显微镜 (TEM) 分析表征反应条件对二氧化硅表面上所得 IL 接枝层的影响。通过熔融混合将 IL 接枝纳米粒子引入聚甲基丙烯酸甲酯 (PMMA) 中，以设计纳米复合材料并证明 IL 接枝纳米粒子分散到聚合物介质中的能力。透射电镜和小角中子散射 (SANS) 证明了 IL 接枝表面对 PMMA 基纳米复合材料形态的作用。结果表明，IL-硅烷的烷基链长度越长，纳米颗粒在PMMA内的分散状态越好。此外，所设计的基于 PMMA 的纳米复合材料具有更好的热稳定性和机械性能，以及新的表面性能。