Nanotubular-aerogel/hydrogel hybrid for strain sensing applications

Abstract

In this research, we introduce a novel nanotubular-aerogel/hydrogel hybrid (NAHH), a promising material for wearable motion sensors, which combines poly(acrylic acid) (PAA) hydrogel with a polypyrrole (PPy) nanotubular-aerogel network to form a hierarchically porous structure. The NAHH outperforms its individual components in terms of mechanical properties, with an fracture toughness of ∼97 kPa for NAHH-1, compared to ∼1.8 kPa and ∼15.3 kPa for PPy nanotubular-aerogel and PAA hydrogel, respectively. The hybrid material also exhibits robust adhesion to a variety of substrates, including porcine skin, with tensile and shear adhesive strengths of ∼54.7 ± 8.4 kPa and ∼58.1 ± 4.4 kPa, respectively. The incorporation of didecyldimethylammonium bromide (DDAB) imbues the NAHH with effective antibacterial properties against both Gram-negative and Gram-positive bacteria. The biocompatibility of the NAHH is further confirmed through a live/dead assay using murine fibroblast 3T3 cells. The NAHH-based motion sensors excel in real-time monitoring of bending and extending motions across various human joints, underscoring their potential for wearable electronic applications. This study presents a versatile platform for the creation of advanced multifunctional materials, with implications for the future of wearable electronics, bioelectronics, and tissue engineering.