填充炭黑对柔性触觉传感器用导电硅橡胶性能的影响

The influence of filled carbon black on the properties of conductive silicon rubber used in flexible tactile sensor

炭黑添加到绝缘的硅橡胶中,制备具有压阻特性的导电硅橡胶是触觉传感器常用的一种材料。通过实验研究3种填充炭黑制成的导电硅橡胶的渗流现象、相同体积分数时压阻特性。显示3种炭黑填充的导电硅橡胶具有不同的渗流阈值,同体积分数下的压阻特性也不相同。相同种类炭黑的添加量改变时,在渗流阈值附近导电硅橡胶的压阻特性最明显。利用扫描电镜(SEM)分析导电硅橡胶的断面形貌,表明导电硅橡胶性能与填料炭黑的分布有关,而炭黑的分布又与其结构相关:粒径越小、表观密度和比表面积越大的高结构炭黑分散性越好,导电硅橡胶的渗流阈值越小,相同体积分数下所获得压阻特性越显著。

Carbon black（CB） filled in insulating silicon rubber to produce the conductive silicon rubber with piezoresistive properties,which is common material to make flexible tactile sensors.Experiments had been conduct to research the percolation phenomenon of the three types of CB,piezoresistive properties of the silicon rubber when the three types of filled CB are at the same content.The result exhibited that the percolation thresholds are different;The piezoresistive properties are different at the same content.Studied the piezoresistive properties of the same type of CB at different contents,discovered that the piezoresistive properties was best when the filler content was at percolation threshold.Scanning electron microscopy（SEM） was used to analysis the cross-section morphology of conductive silicon rubber,the research showed that the conductive performances were related to the dispersion of CB filled in the matrix,which was related to structural characteristics of CB： the smaller the particle size,the greater the apparent density and specific surface area,in other words,higher structure CB would obtain better dispersion,lower percolation threshold and better piezoresistive characteristics.