Research Institute of Forests and Rangelands Iranian Journal of Wood and Paper Science Research 1735-0913 35 2 2020 07 22 The dual function of chitosan on improving the retention of iron oxide nanoparticles and the mechanical strength of magnetic paper produced by in situ synthesis The dual function of chitosan on improving the retention of iron oxide nanoparticles and the mechanical strength of magnetic paper produced by in situ synthesis 205 217 121827 10.22092/ijwpr.2020.342131.1603 FA Shaghayegh Rezanezhad Ph.D. Student of pulp and paper Industry, Agricultural Sciences and Natural Resources of Sari University Hossein Resalati Professor, Department of Wood and Cellulose products. Faculty of Natural Resources, Sari University of Agricultural Sciences and Natural Resources Seyed Majid Zabihzadeh Associate Professor, Department of Wood and Cellulose products. Faculty of Natural Resources, Sari University of Agricultural Sciences and Natural Resources Journal Article 2020 02 29 The most important challenges of using minerals and fillers in the papermaking process are low retention and sharp reduced paper strength properties. In this research, magnetic papers were synthesized using commercial kraft fibers and iron salts. Nano-iron oxide has the same performance as fillers, as a result, to prevent reducing strengths properties and retention of material in the final paper, chitosan uses as a strength agent and retention aid at 0, 10 and 15% levels. Characteristics of magnetic papers were investigated by atomic force microscope, scanning electron microscope, X-ray diffraction and vibration sample magnetometer. Tensile index and tear index were also determined in magnetic paper samples. The results of the microscopic examination showed that the magnetite nanoparticles were in the size range of 1 to 84 nm and the magnetic materials completely covered the fibers surface. Also, increasing chitosan content, increased the degree of loading and magnetic saturation of the samples. The magnetic paper samples had super para magnetic behavior. The results showed that adding chitosan at 10% increased tear and tensile strength but 15% chitosan decreased the strengths properties of magnetic paper. The most important challenges of using minerals and fillers in the papermaking process are low retention and sharp reduced paper strength properties. In this research, magnetic papers were synthesized using commercial kraft fibers and iron salts. Nano-iron oxide has the same performance as fillers, as a result, to prevent reducing strengths properties and retention of material in the final paper, chitosan uses as a strength agent and retention aid at 0, 10 and 15% levels. Characteristics of magnetic papers were investigated by atomic force microscope, scanning electron microscope, X-ray diffraction and vibration sample magnetometer. Tensile index and tear index were also determined in magnetic paper samples. The results of the microscopic examination showed that the magnetite nanoparticles were in the size range of 1 to 84 nm and the magnetic materials completely covered the fibers surface. Also, increasing chitosan content, increased the degree of loading and magnetic saturation of the samples. The magnetic paper samples had super para magnetic behavior. The results showed that adding chitosan at 10% increased tear and tensile strength but 15% chitosan decreased the strengths properties of magnetic paper. https://ijwpr.areeo.ac.ir/article_121827_b464c8e361430885041914a05bf6d188.pdf