Studies on explosion reaction of monovinyl acetylene gas : III. Thermal reaction of monovinyl acetylene gas

Abstract

The thermal reaction of monovinyl acetylene (MVA) was investigated by the admission method at 130mmHg to 460mmHg, and at 300℃ to 400℃. The rapid polymerization reaction was separated from the slow decomposition. The reaction order (2) reaction rate and activation energy (25.3 Kcal/mole) were determined. The structure of cyclobutane or cyclobutene is elucidated for polymer products from the heat of reaction, estimated from the explosion limits and the above rate constant. On the other hand, the main reaction products of decomposition of MVA were found to be hydrogen, ethylene, ethane, methane and small amounts of C_2H_2 with the approximate constant ratio in gaseous phase. Considering these products, the decomposition mechanism is assumed to contain the complete decomposition and the partial decomposition. The explosive reaction at 416℃ was also investigated. The different ratio of the products was found. That the heat evolving reaction induced by the initial polymerization accelerates the decomposition and results in the explosion is presumed.