Piezoresistive strain sensing of carbon black /silicone composites above percolation threshold

Abstract

A series of flexible composites with a carbon black (CB) filled silicone rubber matrix were made by an improved process in this work. A low percolation threshold with a mass ratio of 2.99% CB was achieved. The piezoresistive behavior of CB/silicone composites above the critical value, with the mass ratio of carbon black to the silicone rubber ranging from 0.01 to 0.2, was studied. The piezoresistive behavior was different from each other for the composites with different CB contents. But, the composites show an excellent repeatability of piezoresistivity under cyclic compression, no matter with low filler content or with high filler content. The most interesting phenomena were that the plots of gauge factor versus strain of the composites with different CB contents constructed a master curve and the curve could be well fitted by a function. It was showed that the gauge factor of the composites was strain-controlled showing a promising prospect of application.

Comparison of Pressure Sensing Properties of Carbon Nanotubes and Carbon Black Polymer Composites

“…In the present study, and t calculated using Equation (2) were 0.35 vol.% and 0.92 for CNT/PDMS and 2.13 vol.% and 3.28 for CB/PDMS, respectively. The obtained results ( and t ) follow the same trends as those shown in previous studies [ 20 , 31 , 32 ]. This study observed a lower percolation threshold for CNT/PDMS as compared to that for CB/PDMS.…”

Conductive biofoams of wheat gluten containing carbon nanotubes, carbon black or reduced graphene oxide

“…In the case of the CB foams, the same dependence on the compression strain was observed at smaller carbon black particle contents, but at the highest contents the conductivity increased with increasing strain ( Table 2, conductivity ratios <1), presumably due to a more "crowded" CB system, so that particles came closer together under compression, leading to improved particle-particle interaction and conductance. A similar increase in conductivity with compression of CB particles was earlier reported by Marinho et al and Shang et al 49,50 Fig . 5 shows the conductivity of the rGO/WGG foam under compression.…”

Self‐Healable and Recyclable Tactile Force Sensors with Post‐Tunable Sensitivity

“…Note that the critical fraction (x c ) is remarkably lower than previously reported values (3-20 wt% for CB/ PDMS composites). [35] It could also be explained by the aggregated CB conductive network structure which made the polymer composites conductive even at a relatively low concentration. Figure 2d shows the tensile E-modulus (Young's modulus) of the samples.…”