Back to Search
Start Over
The thermo-oxidation of isoprene containing copolymers of isobutylene: Activation energies and reactions from room temperature to 100 °C.
- Source :
-
Polymer Degradation & Stability . Mar2015, Vol. 113, p55-65. 11p. - Publication Year :
- 2015
-
Abstract
- The activation energies of two poly(isobutylene-co-isoprene) (IIR) copolymers containing 0.9 and 1.85 mol% isoprene were determined under thermo-oxidation conditions from ambient to 100 °C. Transmission Fourier Transform Infrared (FTIR) spectroscopy was used to follow the functional group development. Ketone generation was the dominant oxidative product above 70 °C whereas below this temperature, carboxylic acid formation was prevalent. Non-Arrhenius kinetic behavior was observed due to curvature taking place near 70 °C. The estimated activation energies for the high and low temperature degradation processes were 85–87 kJ/mol and 49 kJ/mol. Test results were interpreted in terms of two competing thermo-oxidative zones, isobutylene and isoprene, the latter operating at low temperatures as shown by isoprene depletion and chain scission reactions. A set of thermo-oxidative reactions for IIR copolymers is proposed comprising allylic and addition reactions at the isoprene unit. [ABSTRACT FROM AUTHOR]
- Subjects :
- *OXIDATION
*POLYMERS
*CHEMICAL reactions
*COPOLYMERS
*TEMPERATURE
*ISOPRENE
Subjects
Details
- Language :
- English
- ISSN :
- 01413910
- Volume :
- 113
- Database :
- Academic Search Index
- Journal :
- Polymer Degradation & Stability
- Publication Type :
- Academic Journal
- Accession number :
- 101932359
- Full Text :
- https://doi.org/10.1016/j.polymdegradstab.2015.01.017