Nanocellulose/poly vinyl alcohol fibres: A green renewable high performance composite

Cellulose nanocrystals (CNC) are promising candidates as stiff fillers in green, renewable, high performance composites, owing to their intrinsic high strength and stiffness. However, historically CNC materials have had low mechanical properties due to CNC aggregation, poor alignment, and low loading fractions. Here, high loadings of water-soluble CNCs are well dispersed in poly vinyl alcohol (PVOH) to form coagulation spinning dopes for composite fibres. The final fibres contain high CNC loading (up to 60 wt. %) while mechanical behaviour is heavily dependent on CNC loading, with tensile strengths approaching the GPa scale at high loadings. The alignment and crystallinity of CNCs and PVOH along the fibre axis was measured by 2D X-ray scattering to account for these differences. This work provides a possible strategy to the challenging question of preparing practical, high performance, green and renewable composites.