Stress‐Normalized Sensitivity as a Comparative Benchmark for Intrinsically Piezoresistive Nanocomposite Materials in Wearable Electronics

ABSTRACT In advanced bioelectronic sensing applications, especially those involving strain and pressure detection, understanding how nanocomposite mechanical properties influence electrical response is critical, yet goes unreported. The two key material properties in this domain are Young's modulus ( Y ) and the piezoresistive gauge factor ( G ). While pressure sensors commonly report device‐level sensitivity as (Δ R / R )/ P ≈ G / Y , here we generalize this relationship into a materials‐level, stress‐normalized figure of merit that integrates intrinsic piezoresistivity, passive mechanical compliance, and Poisson coupling. This stress sensitivity coefficient ( S ) provides a universal, geometry‐independent metric for evaluating piezoresistive nanocomposite materials across strain, pressure, bending, shear, wearable and composite sensor architectures. Although generally treated as separate concepts, with one being mechanical and the other electrical, there is a nuanced connection between the two values, particularly under stress‐controlled conditions. Here, the nature of that relationship within the elastic regime was examined to offer a more complete picture of material suitability in real‐world applications.