Abstract Multiwall carbon nanotubes (MWCNTs) were systematically fragmented using high density ultrasonic energy and used as fillers of a poly (methyl methacrylate) matrix (PMMA). MWCNT fragmentation was confirmed by scanning electron microscopy and atomic force microscopy. Dedicated MWCNT length measurements yielded a log-normal statistical distribution, with mean value of 1.33 μm for the as-received MWCNTs and 0.66 μm for the fragmented MWCNTs. Higher electrical percolation threshold and lower electrical conductivity were obtained for MWCNT/PMMA composites (0.01–1 wt.% MWCNT concentration) using the fragmented MWCNTs. Higher electro-mechanical (piezoresistive) sensitivity under tensile tests was measured for PMMA nanocomposites with fragmented MWCNTs, which was explained by a competition of mechanisms related to the MWCNT length.

中文翻译：

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碳纳米管长度对聚甲基丙烯酸甲酯纳米复合材料压阻响应的影响

摘要 多壁碳纳米管 (MWCNT) 使用高密度超声能量系统地破碎并用作聚甲基丙烯酸甲酯基体 (PMMA) 的填料。通过扫描电子显微镜和原子力显微镜证实了 MWCNT 碎片。专用 MWCNT 长度测量产生对数正态统计分布，原样 MWCNT 的平均值为 1.33 μm，碎片 MWCNT 的平均值为 0.66 μm。使用碎片化的 MWCNTs，MWCNT/PMMA 复合材料（0.01-1 wt.% MWCNT 浓度）获得了更高的电渗透阈值和更低的电导率。对于具有碎片化 MWCNT 的 PMMA 纳米复合材料，在拉伸测试下测量了更高的机电（压阻）灵敏度，这可以通过与 MWCNT 长度相关的机制的竞争来解释。