Preparation and Characterization of Lignosulfonate–Acrylonitrile Copolymer as a Novel Carbon Fiber Precursor

A novel carbon fiber precursor was prepared from lignosulfonate (LS) with acrylonitrile (AN) via a two-step process consisting of esterification and free radical copolymerization. The LS–AN copolymer was characterized by FTIR, 1 H NMR, 13 C NMR, UV, GPC, DSC, and TG. Continuous long precursor fibers with a brown color and a dense structure were prepared from the LS–AN copolymer by a wet spinning technique. Carbon fibers that were free of any visible voids and other defects were also obtained from the precursor fibers by thermal stabilization and carbonization. This study provided a promising way to develop partially biobased carbon fibers with desired mechanical properties for industrial applications.