Accession Number : ADA307833

Title :   Decomposition Characteristics of a Char-Forming Phenolic Polymer Used for Ablative Composites.

Descriptive Note : Technical note,

Corporate Author : NATIONAL AERONAUTICS AND SPACE ADMINISTRATION HAMPTON VA LANGLEY RESEARCH CEN TER

Personal Author(s) : Sykes, George F., Jr

PDF Url : ADA307833

Report Date : FEB 1967

Pagination or Media Count : 24

Abstract : Analysis of the decomposition characteristics of a phenol-formaldehyde polymer by differential thermal analysis, gas chromatography, and elemental analysis has shown the overall process to consist of a series of complex reactions ranging from low-temperature crosslinking (curing) to a high-temperature reaction which results in a carbon char. The energy absorption through decomposition was found to be 293 kJ/kg over the temperature range between 350 C and 850 C. The efflux of volatile products corresponding to this decomposition consisted of components ranging in molecular weight from hydrogen to dimethylphenol (2 to 122). Fifty percent of the total moles identified were hydrogen and 23.4 percent and 10 percent were found to be water and methane, respectively. Analysis of the residue showed that the carbon char appeared over the 400 C to 850 C temperature range concurrent with the formation of volatile oxidized products. The char at 850 C was found to be 92.6 percent carbon, 0.9 percent hydrogen, and 6.5 percent oxygen.

Descriptors :   *POLYMERS, *HEAT SHIELDS, *PHENOLIC PLASTICS, *CHARRING, COMPOSITE MATERIALS, MOLECULAR WEIGHT, CARBON, CROSSLINKING(CHEMISTRY), OXIDATION, ABSORBERS(MATERIALS), VOLATILITY, METHANE, CURING, THERMAL DEGRADATION, GAS CHROMATOGRAPHY, ABLATIVE MATERIALS, ENERGY ABSORBERS, CARBON PHENOLIC MATERIALS, DIFFERENTIAL THERMAL ANALYSIS.

Subject Categories : Laminates and Composite Materials
      Plastics
      Thermodynamics

Distribution Statement : APPROVED FOR PUBLIC RELEASE