Determination of Kinetic Parameters of Six Ablation Polymers by Thermogravimetric Analysis.
Abstract
Six polymers used in ablation heat shield composites were investigated by thermogravimetric analysis (TGA) at temperature-rise rates of 3 K per minute to 18 K per minute in vacuum. These materials were nylon, silicone, polyformaldehyde, and three phenolics. Empirical kinetic parameters were determined for these materials by five different methods (all based on an Arrhenius relation): a direct-solution method, an integral method, a maximum -decomposition method, a multiple-heating -rate method, and a difference method. A best set of parameters was determined for each material by comparing experimental TGA curves with TGA curves derived from the parameters found by each method. The kinetic parameters for the individual materials were shown to satisfactorily describe the mass loss of two composite materials of current interest, a low-density phenolic-nylon and a low-density phenolic-silicone. Direct solution was found to be the most satisfactory method.
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 01, 1967
- Accession Number
- ADA306600
Entities
People
- James B. Nelson
Organizations
- Langley Research Center