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The relative rates of formation of perfluoro iso-propyl radicals (i—C_3F_7,5(i)) and perfluoro n-propyl radicals (n—G_3F_7, 5(n)) are reported. The relative rate constants of β-scission and of bromine abstraction by perfluoro-(α-alkoxyethyl)radicals(RFOCFCF_3:R_F=i—C_3F_7, 3(i); R_F=C_3F_, 3(n)), designated as kr(i) and k,(n), were measured at 7 temperatures in the range of 50—80℃, thence the ratio of the relative rate constants of formation of perfluoro iso-propyl radicals (5(i) and perfluoro n-propyl radicals (5(n)), K_β(i):K_β(n), were obtained. These ratios range from 540—680 at 50℃ to 400—590 at 80℃, much larger than those of the corresponding hydrocarbon radicals. Finally, the differences of activation-free-energy differences between 3(i) and 3 (n), △G~≠(i—n), together with the corresponding enthalpy and entropy terms, △H~≠(i—n), △S~≠(i- n), were calculated. These kinetic parameters indicate that the much higher rate of formation of the perfluoro iso-propyl radicals is caused
The relative rates of formation of perfluoro iso-propyl radicals (i-C_3F_7,5 (i)) and perfluoro n-propyl radicals (n_G_3F_7,5 (n)) are reported. The relative rate constants of β-scission and of (RFOCFCF_3: R_F = i_C_3F_7, 3 (i); R_F = C_3F_, 3 (n)), designated as kr (i) and k, (n), were measured at 7 degrees in the range of 50-80 ° C, thence the ratio of the relative rate constants of formation of perfluoro iso-propyl radicals (5 (i) and perfluoro n-propyl radicals (5 (n)), K_β (i) : K_β (n), were obtained. These ratios range from 540-680 at 50 ° C to 400-590 at 80 ° C, much larger than those of the corresponding hydrocarbon radicals. Finally, the differences of activation-free-energy differences between 3 (i) and 3 (n), △ G ~ ≠ (i-n), together with the corresponding enthalpy and entropy terms, ΔH ~ ≠ (i-n), △ S ~ ≠ . These kinetic parameters indicate that the much higher rate of formation of the perfl uoro iso-propyl radicals is caused