Kinetics study of the gas-phase reactions of CHF2CF2OCHF2 and CF3CHFCF2OCH2CF2CF3 with OH radicals at 253–328 K

The rate constants, k1 and k2, for the reactions of CHF2CF2OCHF2 and CF3CHFCF2OCH2CF2CF3 with OH radicals were measured by means of a relative rate method as (7.58 ± 3.30) × 10−13 exp [−(1720 ± 130)/T] and (8.46 ± 1.83) × 10−13 exp [−(1460 ± 60)/T] cm3 molecule−1 s−1, respectively, at 253–328 K. The measurements were performed in an 11.5-dm3 reaction chamber. OH radicals were generated by UV photolysis of an O3–H2O–He mixture at 200 Torr. The tropospheric lifetimes of CHF2CF2OCHF2 and CF3CHFCF2OCH2CF2CF3 were estimated at 26.5 and 9.1 years.