AUTHORS: Ardath Paige Presler1, Rodney Andrews2, and Terry Rantell2
(1) Natural Science Dept, Transylvania University, KY 40508, fax: 606-233-8171, apresler@mail.transy.edu
(2) Center for Applied Energy Research, University of Kentucky, Lexington, KY 40511
A coal-derived pitch, produced by solvent extraction, was successfully used to produce general purpose carbon fibers. The pitch was characterized by a low softening point of 213C and low ash content. This work explored the effect of spinning temperature on the stabilization, carbonization, and final tensile properties of the fibers. Fibers were spun at several temperatures to determine the effect on the oxidative stabilization of the green fibers. The green fibers were characterized for spinning continuity and brittleness before stabilization. After stabilization, the fibers should remain separable and flexible with sufficient strength to allow handling. Carbonized fibers must retain fiber morphology and are characterized by tensile strength and electric resistivity. These properties rely heavily on the successfulness of the stabilization process. Spinning at a higher temperature was more successful than low temperatures. Spinning temperatures were varied from 230C to 245C, with more rapid stabilization of fibers at higher spinning temperature possible due to oxygen incorporation and polymerization reactions during spinning. The fibers spun at higher temperatures maintain their shape during carbonization even at a rate of 1C per minute versus a maximum carbonization rate of 0.05C per minute for fibers spun at 230C. The more efficient stabilization step would reduce the final fiber cost by lowering the processing costs. Owered costs, faster processing time, and improved tensile properties are found for fibers spun at higher temperatures.