Improving the stability of multiwalled carbon nanotube/silicone rubber composites strain sensors by nanosilica

Conductive polymer composites use elastomers as a matrix for strain sensors. However, elastic polymer composites usually exhibit shoulder peak effects in their resistance response signals, limiting their applicability as strain sensors. In this study, we modified multiwalled carbon nanotubes (MWCNTs)/methyl vinyl silicone rubber (VMQ) by incorporating nanosilica (NSD) to eliminate the shoulder peak effect. The results showed that the addition of a suitable amount of NSD can improve the reconstruction of the conductive network of composite material and eliminated the shoulder peak effect of the composite material in the resistive response signal. The mechanism of eliminating the shoulder peak effect was elucidated, while the mechanical properties of the composite material were improved, which endowed the composite material with excellent strain sensing properties, including sensitivity (GF = 127) and response time (270 ms), and maintained excellent stability and recovery even in 15,000 cycles. These findings highlight the potential of our strain sensor for the real-time strain monitoring of large-deformation isolation bearings.HighlightsNSD eliminates shoulder peak effect in MWCNT/VMQ composites.Explained the shoulder peak effect elimination mechanism.NSD enhanced mechanical properties of MWCNT/VMQ composites.MWCNT-NSD20/VMQ composites have stable resistive strain response properties. Shoulder peak effect and SEM images of MWCNT/VMQ composites modified with different NSD content.image