Preparation of Magnetic Paper from Kenaf: Lumen Loading and in situ Synthesis Method

Abstract

Magnetic papers have been successfully prepared from unbleached kenaf (hibiscus cannabinus) kraft pulps via the lumen loading and in situ synthesis process. The lumen loading method allows the magnetic fillers to be introduced into the lumen of fibres and at the same time leaving the external surfaces free from filler, resulting the better inter-fibre bonding and subsequently its papermaking properties are not affected. Fillers, which deposited in the lumen of fibres will be protected from further mechanical influences. For the lumen loading process, commercial magnetite (Fe₃O₄) powders have been introduced into the lumen by mixing the pulp and magnetic powder. For the in situ synthesis process, nanosized magnetite particles have been precipitated in the presence of pulp fibres and deposited inside the lumen of fibres via chemical coprecipitation process. The samples were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM) and their magnetization properties were examined by a vibrating sample magnetometer (VSM). The loading degree of the papers was estimated by using the Thermogravimetric analyzer (TGA). The VSM results show that the magnetic properties of the lumen loaded papers are higher compared to the in situ synthesis papers in which can be explained that the nanosized magnetite particles possess superparamagnetic properties. However, the SEM micrograph shows that the size and the distribution of the magnetic particles inside the lumen for the in situ synthesis papers are much better than that of the lumen loading papers.