Wang_2022_Carbohydr.Polym_284_119193

An environmental-friendly lipase induced highly hydrophobic NFC film was fabricated through lipase induced dimethyl adipate (DA) esterification followed by silver nanowires (AgNWs) coating for strain sensor application. Due to the lipase activation, the substitution degree (DS(NMR)) of 0.18 was achieved, which was three times higher than that of the control sample (without lipase treatment of NFC-DA). As a result, the water contact angle (WCA) of lipase induced adipated-NFC film was reached to 105 +/- 3 degrees from 50 +/- 2.3 degrees of NFC-DA. In addition, the cellulose structure and performance were well maintained after lipase induced esterification, confirmed by AFM, SEM, TG/DTG, and XRD analysis. After AgNWs coating and annealing, the hydrophobic NFC film-based strain sensor exhibited excellent sensitivity towards human motion, such as finger/wrist movement in real-time, even under wet conditions. Overall, a highly hydrophobic NFC film-based strain sensor was fabricated, which has promising application in wearable devices for human motion monitoring.