Abstract Fracture toughness (FT) and Tensile strength (TS) of epoxy reinforced amine-functionalized MWCNTs (A-MWCNTs)/graphene nanoparticles (GNPs) composites are investigated in cryogenic environment. Simplex centroid design is employed to decide the composition of samples. FT and TS of epoxy improved significantly on incorporating 0.25 wt.% of either A-MWCNTs or GNPs, but increasing the content of nanofillers beyond 0.25% showed lower enhancement in the mechanical properties. Simultaneous addition of nanofillers in epoxy demonstrated synergistic effects, with the maximum FT (121%) and TS (132%) noticed for hybrid composite containing 0.17% of each nanofiller. It is attributed to the presence of well interconnected 3D network between nanofillers and epoxy, which yield uniform dispersion of nanofillers and strong adhesion between nanofillers and epoxy. Regression analysis suggested quadratic models for estimating FT and TS. Multiple response optimization yields the maximum FT (0.907 MPm1/2) and TS (20.6MPa) for hybrid composite containing 99.67% epoxy, 0.17% A-MWCNTS and 0.16% GNPs.

中文翻译：

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石墨烯纳米片和 NH2-MWCNTs 对环氧纳米复合材料低温力学性能的协同作用

摘要 在低温环境中研究了环氧增强胺官能化多壁碳纳米管（A-MWCNTs）/石墨烯纳米粒子（GNPs）复合材料的断裂韧性（FT）和拉伸强度（TS）。采用单纯形质心设计来决定样本的组成。环氧树脂的 FT 和 TS 在掺入 0.25 wt.% 的 A-MWCNTs 或 GNPs 后显着改善，但将纳米填料的含量增加到 0.25% 以上后，机械性能的增强程度较低。在环氧树脂中同时添加纳米填料显示出协同效应，对于包含 0.17% 的每种纳米填料的混合复合材料，注意到最大 FT (121%) 和 TS (132%)。这归因于纳米填料和环氧树脂之间存在良好互连的 3D 网络，这产生纳米填料的均匀分散和纳米填料和环氧树脂之间的强粘附。回归分析提出了用于估计 FT 和 TS 的二次模型。对于含有 99.67% 环氧树脂、0.17% A-MWCNTS 和 0.16% GNP 的混合复合材料，多响应优化产生最大 FT (0.907 MPm1/2) 和 TS (20.6MPa)。