Wet spinning of low cost carbon fiber precursor-lignin incorporated polyacrylonitrile co-polymer fiber

Low cost carbon fiber from lignin is a promising biobased feedstock since lignin is by product in many industries. In the present work spinning of concentrated solution of lignin blended with polyacrylonitrile copolymer have been investigated. The wet spinning experiments of PAN/Lignin blend solution to obtain the precursor fiber in continuous form have been successfully demonstrated. Rheological measurements are carried out to optimize the wet spinning process parameters such as to ascertain the dissolution and extrusion temperature. The gel formation temperature of PAN/Lignin blend solutions are determined by the plot of tan δ Vs temperature plot. The FTIR analysis confirms that there is no discernible chemical reaction or crosslinking between PAN and lignin. The resulting precursor fiber from PAN/Lignin blend solution displayed a tensile strength and modulus of 2.36 gpd and 76 gpd respectively.