The rate coefficient of the C₃H₃ + C₃H₃ reaction-dipropargyl oxalate as a new source for C₃H₃ radicals

Much attention is paid to the self reaction of propargyl radicals (C₃H₃) as an important source for C₆H₆ species under fuel-rich conditions. To obtain halogen-free reaction systems, the use of dipropargyl oxalate as a new, clean source for C₃H₃ radicals was studied. The transient UV absorption after laser-flash photolysis of dipropargyl oxalate at 193 nm was studied and found that the initial absorption between 310 and 360 nm corresponded to the C₃H₃ spectrum in the literature. The absorbance-time profiles recorded at the absorption maximum of 332.5 nm could be reproduced by a second-order rate law with a rate coefficient of (5.5 × 10^-11 cc/molecule-sec independent of total pressure (1-150 bar) and temperature (373-425 K). Original is an abstract.