Superelastic and Ultralight Aerogel Assembled from Hemp Microfibers

摘要

Aerogels with both high elastic strain and fast shape recovery after compressionhave broad application potentials as thermal regulation, absorbents, andelectrical devices. However, creating such aerogels from cellulosic materialsrequires complicated preparation processes. Herein, a simple strategyfor scalable production of hemp microfibers using a top-down method isreported, which can further be assembled into aerogels with interconnectedporous structures via ice-templating technique. With density as low as2.1 mg cm~(?3), these aerogels demonstrate isotropic superelasticity, as exhibitedby their fast shape restoration from over 80 compressive strain. Dueto the high porosity (99.87) and structural tortuosity, these aerogels showa low thermal conductivity of 0.0215 ± 0.0002 W m~(?1) K~(?1), suggesting theirpotential in thermal insulation application. Certain hydrophobic modificationusing silane derivative further endows these aerogels with reduced wateraffinity. Overall, the proposed strategy to prepare bio-based microfibers usingscalable technology, as well as the assembled aerogels, provides new insightsinto the design and fabrication of multifunctional bio-based aerogels forvalue-added applications.