Abstract

Currently, due to the great advances achieved in medicine, together with those related to materials science and engineering, in recent years there has been a growing interest in the use of flexible sensors for monitoring the human body. The present work shows the development of flexible piezoresistive sensors based on polyvinylidene fluoride (PVDF) reinforced with carbon nanotubes (CNTs). First, the analysis of the electrical properties shows an increase in the electrical conductivity with CNT content. This increase is less pronounced at higher CNT contents due to an electrical network saturation, where the main electrical transport mechanisms are dominated by the CNT aggregates. In this context, the electromechanical analysis shows a higher sensitivity, by means of Gauge Factor, at lower CNT contents due to a higher prevalence of tunneling transport mechanisms between neighboring nanoparticles, which is reflected in a more exponential electromechanical behavior. Finally, the analysis of the electromechanical properties at cycling loading shows an elevated repeatability of the electrical response between consecutive cycles, which is indicative of the high robustness of the manufactured sensors.