Biopolymer composite fibres composed of calcium alginate reinforced with nanocrystalline cellulose

To improve the mechanical performance of alginate fibres, cellulose nanocrystal (CNC) and its oxidized derivative (OCNC) were employed separately as the reinforcing nanofillers to prepare complete polysaccharide-based biocomposite fibres. Comparative studies indicate that both CNC and OCNC can effectively improve the mechanical performance of calcium alginate fibre at a lower content than 3.0 wt.% with an optimum effect observed at 0.5 wt.% loading. Both of them can enhance the water absorbency of calcium alginate fibre. CNC is more effective than OCNC to improve the mechanical property and water absorbency. Although a minor reduction in the flame retardancy of the resultant fibres was observed, in particular by the addition of CNC, the nanocomposite fibres still display good flame retardant properties, with the limiting oxygen index beyond 30. The good mechanical performance, water absorbency, and satisfactory flame retardancy of the resultant nanocomposite fibres is advantageous for their applications in different occasions.