Akademik Veri Yönetim Sistemi
Journal of the Faculty of Engineering and Architecture of Gazi University, cilt.40, sa.2, ss.749-760, 2025 (SCI-Expanded)
In this study, the structural changes of viscose rayon fiber, which is one of the regenerated cellulose fibers, in the thermal stabilization stage before the carbonization stage were investigated. Viscose rayon fibers were soaked in 4% phosphoric acid aqueous solution at room temperature for 30 min. It was subjected to chemical pretreatment and then heat treated at different stabilization (oxidation) temperature values (150℃-175℃-200℃-225℃ and 250℃) after the pre-drying process. On the samples after thermal stabilization; Changes in some physical and structural properties such as yarn count measurement, color change analysis, density, microscopic fiber thickness study and yarn strength were investigated. In addition, combustion test, SEM, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and infrared (FTIR) spectroscopy measurements and mechanical tests were performed for the structural characterization combination of the samples. It was determined that yarn count and fiber thickness decreased depending on the increase in thermal stabilization process temperature. However, after the thermal stabilization processes, the appearance of the viscous rayon samples changed from white color to carbon black, while it was found that the samples became non-flammable at 225℃ and 250℃. In the strength analysis, tensile strength and elongation at break decreased up to the stabilization temperature of 225℃, while a partial increase was observed after the stabilization process at 250℃. Depending on the stabilization temperature, the decomposition endotherm decreased due to the changes in the crystal structure of the stabilization samples as the temperature increased, and the decomposition endotherm almost disappeared at 250℃ thermal stabilization.