Details

Autor(en) / Beteiligte

• Arisawa, H.
• Brill, T.B.

Titel

Flash pyrolysis of hydroxyl-terminated polybutadiene (HTPB) II: Implications of the kinetics to combustion of organic polymers

Ist Teil von

• Combustion and flame, 1996-07, Vol.106 (1), p.144-154

Ort / Verlag

New York, NY: Elsevier Inc

Erscheinungsjahr

1996

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• The first semi-micro kinetics analysis is described for rapid pyrolysis of an organic polymer. T-Jump/FTIR spectroscopy and structurally different hydroxyl-terminated polybutadiene polymers (HTPB) were used. The rates of formation were determined for the six most prevalent volatile products from HTPB heated at 600°C/s to constant temperatures in the 450°–609°C range under 2 and 11 atm of applied pressure. The resulting Arrhenius parameters reveal that mildly exothermic, bulk-phase, heterogeneous decomposition reactions control the rate of gaseous product evolution at T < 500°–530°C under 2 atm Ar. The exact temperature depends on the product and the polymer microstructure. The rate evolution of most of the gaseous products at T > 500°–530°C is controlled by desorption of fragments of the polymer rather than bulk-phase decomposition. When P = 11 atm Ar, the formation and desorption of these fragments controls the rate of product of evolution over the entire 460°–600°C range. These individual rate constants combined into a single rate yield macro kinetics of gas evolution from R45M as follows: E a = 51 kcal/mol, ln A (s −1) = 31 for 2 atm and 450°–530°C; E a = 18 kcal/mol, ln A (s −1) = 11 for 2 atm and 530°–609°C; E a = 12 kcal/mol, ln A (s −1) = 6.6 for 11 atm and 460°–600°C. A generalized equation that qualitatively matches the kinetics of gaseous product evolution as a function of pressure is given.