EFFECT OF SPINNING CONDITIONS ON STRUCTURES OF PITCH-BASED CARBON-FIBER

Carbon fibers were prepared from mesophase pitch by spinning using sev eral types of nozzles, with different shapes and sizes of cross sectio ns of the pitch reservoir, with or without a fine mesh filter on it. M acrostructure in the transverse section of the carbon fibers was a dis torted radial type when the shape of cross section was not circular. S uch a nozzle with a mesh filter was found to make the microstructure f iner and to depress the development of the three-dimensional ordering of crystallites of carbon fibers. This new type of nozzle with a mesh filter also improved tensile strength of the carbon fibers.