Recent safety considerations have sought to lower the electrical conductivity of carbon fibers. Carbon fibers produced from polyacryonitrile at low carbonization temperatures (600°-900°C) possess low electrical conductivity but do not possess adequate strength. Low-temperature processes are described which improve fiber strength but do not increase electrical conductivity substantially. The processes result in a carbon fiber with nearly twice the tensile strength compared to the old process. Process development and its effect on fiber properties are reported.
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