(698f) Carbon Fiber Derived from PAN/Lignin Bi-Component Precursor

Jing Jin, Amod A Ogale

Department of Chemical and Biomolecular Engineering

Center for Advanced Engineering Fibers & Films (CAEFF)

Clemson University, Clemson, SC 29634

Abstract

Bio-derived precursors are of increasing interest in the production of carbon fibers to reduce the reliance on synthetically-derived polyacrylonitrile (PAN) precursor, which is primarily used in current commercial carbon fibers.  Lignin, an abundant biomass, is currently recycled back into paper production process. However, there are renewed efforts to find value-added applications for lignin, including that as a carbon fiber precursor.  Several studies have been reported on the conversion of chemically-modified lignin into carbon fibers.  However, the tensile strength of such fibers has been limited to about 1 GPa. Therefore, the current study investigates the processing and properties of carbon fibers derived from bi-component lignin and PAN precursors.

PAN and softwood kraft lignin were wet-spun into precursor fibers. Hydroxyl groups in lignin enable the solubility in DMSO (solvent) for wet spinning and higher rate of thermal stabilization. Carbon fibers were successfully produced by heat-treatment in inert environment at 1000°C.  The properties of such fibers are much lower than those derived from conventional PAN fibers.  This observation is consistent with other limited studies on PAN/lignin polymer blends. Essentially, the lignin component was not found to contribute to the strength of resulting carbon fibers. Therefore, ongoing studies are dealing with alternative routes for processing PAN/lignin, including two different layers to form a bi-component precursor fiber.

Key Words: Carbon fiber, Lignin, Wet spinning