Thermal degradation and isothermal crystallization behavior of Curdlan propionate and its melt-spinning fiber

Abstract The thermal properties and crystallization kinetics of Curdlan propionate, a type of bio-based plastic and β-1,3-glucan derivative, were investigated. Melt-spun fibers were also prepared, and the fiber formation mechanism and internal structure were analyzed. The decrease curve in molecular weight suggests that the thermal degradation of Curdlan propionate likely proceeds by random scission. Polarized light microscopy of the isothermal crystallization process showed Curdlan propionate forms a spherulite-like morphology, which is unusual among polysaccharides with a rigid backbone chain. By optimizing the melt spinning conditions, it was found that it is possible to spin with good spinnability using a no plasticizer. The crystallization rate of Curdlan propionate was significantly different between the isothermal crystallization process and the melt spinning process. There was a positive correlation between the take-up speed, crystallinity, and the tensile strength of the fiber. A highly ordered structural model of the fiber was suggested from wide-angle x-ray diffraction results and other measurements.