Development of a high-strength carrageenan fiber with a small amount of aluminum ions pre-crosslinked in spinning solution

Abstract In this work, an improved wet spinning method was proposed to prepare high-tensile-strength carrageenan fibers by pre-crosslinking process. Pre-crosslinking was achieved by adding a small amount of Al 3+ ions into the spinning solution. The properties of the carrageenan spinning solution were analyzed by polarizing microscope, dynamic light scattering, and viscosity, the results showed that the modified spinning solution pre-crosslinked with Al 3+ ions was orderly and high-viscosity, and the average particle size of the spinning solution was increased. The properties of the carrageenan fibers were characterized using scanning electron microscope, Fourier transform infrared spectroscopy, X-ray diffraction spectroscopy, X-ray photoelectron spectroscopy, and tensile tests. The results showed that the new carrageenan fibers were formed by coordination and ionic bonds between Al 3+ , –OH and sulfate groups. The tensile strength was up to 1.77 cN/dtex of Al-3.0/CAF (the best of newly prepared carrageenan fiber in this work), which is the highest strength carrageenan fiber prepared at present. Compared with the traditional process, this method reduced the concentration of Al 3+ ions in coagulation bath and stretch bath, thus saving the production cost and protecting the environment.