State Key Laboratory of Precision Measurement Technology and Instruments, Department of Precision Instrument, Tsinghua University, Beijing 100084, People’s Republic of China.
Nanotechnology. 2013 Jul 5;24(26):265704. doi: 10.1088/0957-4484/24/26/265704.
Carbon nanotubes (CNTs) filled polymeric composites can be used as a kind of flexible piezoresistive material in potentially many fields. Due to the diversity of CNTs and polymers, the mechanism and features of their piezoresistive behaviour is still not fully understood. This paper reports our investigations into the mechanism and optimization of piezoresistive CNT/polymer composites. Numerical simulation results showed that the junction resistances between CNTs are a major component of the network conductance of the composite as well as the piezoresistive behaviour. Average junction gap variation (AJGV) was introduced as a quantitative description of the conductance variation of a CNT network caused by strain and the conductance variation of the CNT network was found to be dominated by AJGV. Numerical simulation and analytical results indicated that the key parameters affecting AJGV include the orientation and diameter of CNTs, Poisson’s ratio of the polymer, and the concentration of CNTs in the polymer matrix. An optimizing principle was then given for piezoresistive CNT/polymer composites.
碳纳米管（CNTs）填充聚合物复合材料可用作潜在许多领域的一种柔性压阻材料。由于 CNTs 和聚合物的多样性，其压阻行为的机制和特征尚不完全清楚。本文报道了我们对压阻 CNT/聚合物复合材料的机制和优化的研究。数值模拟结果表明，CNTs 之间的结电阻是复合材料网络电导率以及压阻行为的主要组成部分。平均结间隙变化（AJGV）被引入作为应变引起的 CNT 网络电导率变化的定量描述，并且发现 CNT 网络的电导率变化主要由 AJGV 决定。数值模拟和分析结果表明，影响 AJGV 的关键参数包括 CNTs 的取向和直径、聚合物的泊松比以及聚合物基体中 CNTs 的浓度。然后给出了压阻 CNT/聚合物复合材料的优化原则。
