Out-of-Plane Auxetic Behavior in Cellulose Nanofibril Films.

ABSTRACT: While auxeticity has been established in cellulose-based paper and paperboards and computational studies suggest auxetic behavior should occur within cellulose structures, the auxetic response of neat cellulose nanofibril (CNF) films has not yet been experimentally established. Here, we show that an out-of-plane auxetic response does occur in CNF films and that the magnitude of the response is dependent on the film density, microstructure, and sample geometry. CNF films are fabricated using vacuum filtration, followed by conditioning at 23 °C and 50% relative humidity. The CNF aqueous suspension amount is varied from 90 to 450 mL, which progressively increases the film density until reaching a plateau of 1.05 ± 0.02 g/cm³ for films with suspension volumes equal to or greater tha

SUBMITTER: Rubaiya F 

PROVIDER: S-EPMC11983352 | biostudies-literature | 2025 Apr

REPOSITORIES: biostudies-literature