Electrical Resistivities of PVA/Activated Carbon-Based Hydrogels

This study investigates the physical and electrical properties of the polyvinyl alcohol (PVA) hydrogel incorporated with edible Activated Carbon (AC). Three samples, namely PVA, PVA/AC 0.5, and PVA/AC 1.0 were prepared using the freeze-thaw method. The samples underwent six freeze-thaw cycles, each consisting of freezing at –25°C for 20 hours and subsequent exposure to room temperature for 4 hours. The porous network of hydrogel is attributed to the hydroxyl groups of PVA, resulting from the intermolecular cross-linking of PVA chains. The edible AC was uniformly dispersed within the hydrogel network, leading to a reduction in hydrogel pores. As a result, the electrical resistivity of PVA, PVA/AC 0.5, and PVA/AC 1.0 hydrogels measured 1052.9 ± 165.0 Ω.cm, 403.1 ± 29.2 Ω.cm, and 59.9 ± 4.7 Ω.cm, respectively. The incorporation of edible AC significantly decreased the resistivity of the hydrogel. So, this hydrogel is promising for biomedical and edible electronics applications.