Almond shell nanocellulose: Characterization and self-assembling into fibers, films, and aerogels

Cellulose has been efficiently isolated from almond shell (AS) of a soft-shell Carmel variety by two-step NaClO2 oxidation-KOH alkali protocol at over 35 % yield, then optimally TEMPO-oxidized and blended to yield 92 averagely 1.2 nm high (H), 5.2 wide (W), 1.4 µm long (L) cellulose nanofibers (CNFs) with 58.6 crystallinity 1.3 mmole/g charge. With uniquely 1167 L/H aspect ratio 4.3 W/H lateral anisotropy, AS CNFs self-assembled into 1D fibers 3D aerogels freezing ? 196 °C 20 °C, respectively, lyophilization as well 2D films air drying. All were fully re-dispersable in water individualized whereas amphiphilic super-absorbents, absorbing slightly more hydrophobic chloroform than water, hydrophilic on the surfaces absorbed ca. three times decane. The aqueous dispersible fibers, resilient aerogels, organic are attributed interfacial associations CNF driven their cross-sectional demonstrating processing potential versatile materials.