Abstract Inspired by nature, nanocarbon black (nCB) was diffused into swollen polydimethylsiloxane (PDMS) to obtain flexible conductive composites, forming a gradient distribution morphology. The nCB was enriched in the surface layers and its loading decreased in the inner region and the distribution process was theoretically calculated. The mechanical properties of PDMS/nCB composites were close to those of pure PDMS due to the gradient nCB distribution, and the surface of PDMS/nCB presented super-hydrophobicity resulted from the rough surface, even under strains. The composite started to be conductive at only 0.8 wt% nCB and it could work at a strain of 355% and had gauge factor of 343 with 6.2 wt% CB loading. The resistance of the composites against strain was explained theoretically using models based on the constriction and tunneling effects. These results indicate that composites with gradient filler distribution are excellent candidates for use as flexible strain sensors with high performance.

中文翻译：

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基于梯度填料分布的高性能柔性应变传感器仿生设计

摘要 受自然界启发，将纳米炭黑（nCB）扩散到溶胀的聚二甲基硅氧烷（PDMS）中，得到柔性导电复合材料，形成梯度分布形态。nCB在表层富集，在内部区域负载减少，理论上计算了分布过程。由于nCB的梯度分布，PDMS/nCB复合材料的力学性能接近纯PDMS，并且PDMS/nCB的表面呈现出由于表面粗糙，即使在应变下也具有超疏水性。该复合材料在仅 0.8 wt% nCB 时开始导电，它可以在 355% 的应变下工作，并且在 6.2 wt% CB 负载下具有 343 的应变系数。使用基于收缩和隧道效应的模型从理论上解释了复合材料的抗应变能力。