1826-76-2Relevant academic research and scientific papers
KINETICS OF REACTIONS OF C3., C5. AND C7. ALKYL RADICALS FORMED IN THE CF3. + C2H4 SYSTEM, I. DETERMINATION OF THE RATE COEFFICIENTS
Dobe, Sandor,Berces, Tibor,Marta, Ferenc
, p. 43 - 58 (2007/10/02)
n-Propyl, n-pentyl and n-heptyl free radicals (with perfluorinated methyl groups) were generated by the photolysis of perfluoroacetic anhydride (PFAA) in the presence of ethylene.Reaction products up to dodecanes were identified and measured under various experimental conditions, i.e. at different ethylene concentrations, / ratios, reaction temperatures and incident light intensities.Disproportionation/combination ratios were obtained for the n-propyl, n-pentyl and s-heptyl free radicals.The rates of addition of the C3. and C5. radicals were studied at 300 and 362 K.The rate coefficient ratios kaddition/kcombination1/2 of (4.04+/-0.69)E-3 and (2.72+/-0.66)E-3 dm3/2 mol-1/2 s-1/2 were determined at room temperature for the n-propyl and n-pentyl radicals, respectively.The activation energies obtained were 27.8 kJ mol-1 for C3. addition and 26.8 kJ mol-1 for C5. addition.Isomerisation of the n-heptyl radical by 1,5-hydrogen shift was observed to occur and the isomerization rate coefficient relative to that of C7. self-combination, kisomeriz/kcomb1/2=(5.8+/-1.0)E-5 mol1/2 dm-3/2 s-1/2, was determined at room temperature.The kinetic results for addition and isomerization reactions are discussed in the light of available literature data.
