Strong highly anisotropic magnetocellulose nanocomposite films made by chemical peeling and in situ welding at the...

Magnetic cellulosic papers have attracted considerable interest because of their potential applications in advanced information storage devices and security papers. However, these papers are often mechanically weak and structurally and magnetically in-plane isotropic, which restrict their applications especially where stronger anisotropic materials are required. Here, we report the production and properties of a strong anisotropic superparamagnetic cellulose nanocomposite (ASPCNC) film with high in-plane anisotropy prepared using ionic liquid (IL)-based peeling and in situ welding processes. Field-emission scanning electron microscopy, energy-dispersive X-ray analysis, X-ray diffraction, attenuated total reflection Fourier transform infrared spectroscopy, atomic force microscopy, magnetic force microscopy, and vibrating sample magnetometry were used to characterize the produced nanocomposite films. Mechanical and magnetic in-plane anisotropy were measured, and their relationships with the structural properties were determined. Tensile failure behavior of the ASPCNCs was also compared with predictions from Hankinson's failure model. The results show highly significant relationships between increasing partial dissolution time as the development index of the IL-based peeling and in situ welding procedures and improvements in the mechanical properties and structural, mechanical, and magnetic in-plane anisotropy of the ASPCNCs. Reasons behind these observations are extensively discussed.