Thermal decomposition of azoisopropane. I. Primary decomposition processes

The thermal decomposition of azoisopropane (AIP) was studied by detailed product analysis in the temperature and pressure intervals 498–563 K and 0.67–5.33 kPa. Besides the predominant termination and hydrogen‐abstraction reaction of the 2‐propyl radical, the decomposition is characterized by a very short chain process. The following rate constants were determined from the measurements\documentclass{article}\pagestyle{empty}\begin{document}$$\begin{array}{rcl} \log (k_1 {\rm /s}^{ - 1} ) &=& (16.3 \pm 0.2) - (199.9 \pm 1.6){\rm kJ mol}^{ - 1} /2.3RT \\ \log (k_4 /k_3^{1/2} {\rm dm}^{{3 \mathord{\left/ {\vphantom {3 2}} \right. \kern-\nulldelimiterspace} 2}} {\rm mol}^{{{ - 1} \mathord{\left/ {\vphantom {{ - 1} 2}} \right. \kern-\nulldelimiterspace} 2}} {\rm s}^{{{ - 1} \mathord{\left/ {\vphantom {{ - 1} 2}} \right. \kern-\nulldelimiterspace} 2}} ) &=& (4.1 \pm 0.3) - (52.5 \pm 3.0){\rm kJ mol}^{ - 1} /2.3RT \\ \log (k_5 /k_3^{1/2} {\rm dm}^{{3 \mathord{\left/ {\vphantom {3 2}} \right. \kern-\nulldelimiterspace} 2}} {\rm mol}^{{{ - 1} \mathord{\left/ {\vphantom {{ - 1} 2}} \right. \kern-\nulldelimiterspace} 2}} {\rm s}^{{{ - 1} \mathord{\left/ {\vphantom {{ - 1} 2}} \right. \kern-\nulldelimiterspace} 2}} ) &=& (2.4 \pm 0.1) - (27.6 \pm 1.3){\rm kJ mol}^{ - 1} /2.3RT \\ k_2 /k_3 &=& 0.51 \pm 0.02 \end{array}$$\end{document}for the following reactions: