Speaker
Description
Innovative strategies to tailor the structure and architecture of nanocellulose-based films are needed to enhance their performance regarding mechanical and optical properties for sustainable applications in bioengineering, sensors, and advanced materials. Both cellulose nanofibers (CNFs) and cellulose nanocrystals (CNCs) self-assemble into liquid crystalline phases with nematic and chiral nematic ordering, respectively. The mechanical and optical properties of the derived films strongly depend on this ordering. Our strategy to produce nanocellulose films with tailored structure and architecture involves combining osmotic dehydration, in-situ magnetic fields, and adjusting the CNC-CNF ratio. The alignment is controlled by both the intensity and direction of the applied magnetic field, resulting in anisotropic films with designed architectures in conjunction with osmotic dehydration. The magnetic alignment and structural features of the CNCs (including both isotropic and anisotropic fractions) are studied using polarised light optical imaging, Small Angle X-ray Scattering (SAXS, including in-situ magnetic field), and UV-Vis spectroscopy, while their viscoelastic properties are examined by rheology. The overall morphology of the CNF-CNC layered film is analysed with Scanning Electron Microscopy (SEM). Ultimately, combining osmotic pressure and magnetic fields, along with adjusting the CNC-CNF ratio, opens new opportunities for nanocellulose-based materials in developing tailored and designed physical-chemical properties.