Investigation on spinnability of low molecular weight alkaline lignin to fabricate biobased carbon fiber

Using acetic acid instead of dimethylformamide as solvent, lignin-based nanofibers were prepared by electrospinning with industrial low molecular weight lignin. After pre-oxidation and carbonization, the fibril was transformed into carbon fiber. The results showed that different viscosity of spinning solution and different parameters of electrospinning have great influence on the morphology of fibers. The diameter of fibers could be concentrated in 300-500nm by using the best electrospinning process. After carbonizing the fibers, it was found that the lignin fibers could retain the morphology of the fibers after carbonization at a suitable heating rate and holding temperature. This study showed the conditions required for the preparation of carbon fiber from low molecular weight lignin, and provided a way for high value utilization of waste biomass and green preparation of carbon fiber.