Piezoresistivity, Strain, and Damage Self‐Sensing of Polymer Composites Filled with Carbon Nanostructures

Abstract

Previous and current research on piezoresistivity of polymer composites filled with carbon nanostructures is reviewed. The review covers the use of the coupled electro‐mechanical response of these materials to self‐sense their strain and damage during mechanical loading. The mechanisms yielding changes in electrical resistance upon mechanical loading in polymer composites filled with carbon nanostructures are first discussed. Published knowledge is then summarized, starting with framework literature on carbon black and graphite and then moving to more recent research on carbon nanotubes, exfoliated graphite, and few‐layer graphene sheets. Piezoresistive studies of polymer nanocomposites with aligned carbon fillers are also reviewed. It is aimed that this review contributes in collecting, organizing, and summarizing the knowledge, foundations, and state of the art on the piezoresistive response of polymer composites filled with different carbon allotropes, providing new perspectives and advancing towards the fast development of smart self‐sensing carbon filled nanocomposites.

Preparation and Characterization of Polypropylene/Carbon Nanotubes (PP/CNTs) Nanocomposites as Potential Strain Gauges for Structural Health Monitoring

“…For this reason, a viable strategy can be the use of polymer/CNTs nanocomposites as sensing materials. Indeed, several polymer/CNTs nanocomposites have been previously investigated and tested as strain-sensors, exploring the use of different polymer matrices: epoxy resin [32][33][34], polymethyl methacrylate [35] and polypropylene [36][37][38][39][40][41][42]. Polymer/CNTs are excellent sensing materials if the electrical percolation threshold (EPT) is exceeded.…”

“…Even if several authors investigated sensing ability of PP/CNT alone [36][37][38][39][40][41][42], to the best of our knowledge, no studies investigated the possibility to use PP/CNT strain sensors directly embedded in cementitious materials. Several authors proposed the use of sensing skins or sensing elements to be applied on external surfaces of buildings/infrastructures [53][54][55][56][57].…”

Design of Active Interfaces Using Responsive Molecular Components

“…Since the surface of a material is where it connects to its environment, a similar trend from “passive” to “active” interfaces is leading to functional interfaces that respond to external stimuli and enable versatile material interfaces with tunable and reversible properties such as wettability and adhesion . Potential applications are found in a wide range of areas such as electronics and energy materials, biotechnology and biomaterials, sensing, additive manufacturing, and many more …”

Earthquake‐induced damage detection and localization in masonry structures using smart bricks and Kriging strain reconstruction: A numerical study

“…Applications of smart concretes comprise the development of integral smart structures, embedded strain sensors, as well as superficial sensors or smart skins . Also promising are self‐sensing polymer composites for the development of large surface strain sensors and stretchable electronics . It is worth noting the work by Laflamme et al, who proposed low‐cost soft elastomeric capacitor strain transducers in combination with a Kriging interpolator for damage identification in wind turbine blades.…”

“…25 Also promising are self-sensing polymer composites for the development of large surface strain sensors and stretchable electronics. 26 It is worth noting the work by Laflamme et al, 27 who proposed low-cost soft elastomeric capacitor strain transducers in combination with a Kriging interpolator for damage identification in wind turbine blades. Although many authors have striven to apply smart materials to concrete or aerospace structures, the number of attempts to bring this concept to masonry structures is very scarce.…”