Accession Number : AD0906471
Title : Exploratory Development of Low Thermal Conductivity Carbon Fibers.
Descriptive Note : Final technical rept. 1 Jun 71-31 May 72,
Corporate Author : CELANESE RESEARCH CO SUMMIT NJ
Personal Author(s) : Kalnin, Ilmar L. ; Ram, Michael J. ; Dix, Robert
Report Date : NOV 1972
Pagination or Media Count : 125
Abstract : The objectives of this exploratory program were to develop techniques for producing high strength, high modulus graphite or carbon fibers of low thermal conductivity and to develop an instrument for measuring the thermal conductivity of the presently available fibers as well as the experimental fibers developed. An apparatus for determining low order thermal conductivities of small amounts of fiber was designed, built and proven reliable for testing fibers with thermal conductivities as low as 0.015 cal/cm. sec. C. A correlation was found between electrical resistivity of the fiber and its thermal conductivity. Chemical intercalation of carbon fibers using hot nitric and sulfuric acids resulted in a substantial decrease in thermal conductivity. Carbonization at low temperatures of polyacrylonitrile fibers containing carbon black yielded lower thermal conductivity but reduced strength at the same time because of the presence of large carbon particles. Addition of soluble additives to the spinning dope did not give a spinnable solution which could be converted to carbon fibers having lower conductivity. (Author-PL)
Descriptors : (*CARBON FIBERS, THERMAL CONDUCTIVITY), BORON, GRAPHITE, ACRYLONITRILE POLYMERS, ELECTRICAL RESISTANCE, TENSILE PROPERTIES, SPINNING(INDUSTRIAL PROCESSES), ADDITIVES, MICROSTRUCTURE, HEAT TREATMENT, ETCHING, THERMOCOUPLES, DOPING, COATINGS, MODULUS OF ELASTICITY, NITRIC ACID, SULFURIC ACID, REINFORCING MATERIALS, HEAT SHIELDS, SYNTHETIC FIBERS, OXIDATION, MANUFACTURING, INSTRUMENTATION.
Subject Categories : Textiles
Distribution Statement : APPROVED FOR PUBLIC RELEASE