PRODUCTION OF CARBON FIBER

摘要

PURPOSE:To improve the quality of carbon fiber while decreasing the deposition in a furnace and suppressing the fluffing of fiber bundle by applying a water-soluble polymeric substance to a flame-resistant acrylonitrile fiber bundle and introducing the bundle into a carbonization furnace. CONSTITUTION:An acrylonitrile fiber is oxidized in an oxidizing atmosphere to obtain a flame-resistant acrylonitrile fiber bundle. A liquid containing one or more water-soluble polymeric substances selected from polyvinyl alcohol, polyethylene oxide and polyacrylamide is applied to the fiber bundle and dried at <=250 deg.C to attach 0.1-2.0wt.% of the polymeric substance to the fiber bundle. The coated bundle is introduced into a carbonization furnace heated at >=400 deg.C to obtain the objective carbon fiber. Since no clogging occurs in the carbonization furnace, the operation can be continued over a long period to improve the operation efficiency.