“…Cellulose is one of the most abundant renewable materials that has been extensively used in paper, packaging, food, textile, and biomedical industries. It is hydrophilic, but insoluble in water and most common solvents, because of strong hydrogen bonds between the cellulose molecular chains. − Recently, cellulose has been drawing attention in the form of nanocellulose, such as cellulose nanofibrils (CNF) and cellulose nanocrystals (CNC) for mechanical reinforcement of hydrogels, because of their very high aspect ratios, as well as for their high moisture absorptivity, wettability, and renewability . Both CNF and CNC are composed of β (1–4) linked d -glucose units with semicrystalline structures and exhibit impressive mechanical properties and tunable surface chemistry and reactivity through chemical modifications. , The enhancement of mechanical strength has great potential for cellulose-based strain sensors. − The incorporation of CNF with PVA in hydrogel sensor has been reported for the synthesis of transparent, stretchable, and rapid self-healing hydrogel sensors .…”