Determination of the Octanol−Air Partition Coefficients (KOA) of Fluorotelomer Alcohols

Octanol−air partition coefficients ( K OA ) for five fluorotelomer alcohols (4:2 FTOH, 6:2 FTOH, 8:2 FTOH, 10:2 FTOH, and for the first time 12:2 FTOH) were determined over a temperature range from (5 to 40) °C using a modified generator column method. Octanol-saturated air at a fixed temperature was blown over a column filled with glass spheres which were coated with an FTOH solution. FTOHs partitioning to the gas phase were collected on a trap filled with XAD-2 and eluted with acetone afterward. The concentrations of FTOH were measured by GC-MS using positive chemical ionization. The K OA values were calculated as the ratio of the FTOH concentrations in the octanol to the FTOH concentrations in the air. Values of log K OA at 25 °C ranged from 4.5 (4:2 FTOH) to 6.2 (12:2 FTOH). The calculated internal energies of phase change (Δ U OA ) ranged from 42.8 kJ·mol −1 (12:2 FTOH) to 61.1 kJ·mol −1 (4:2 FTOH). The combined uncertainty of the method applied ranged from 8.3 % (4:2 FTOH) to 10.5 % (10:2 FTOH). The expanded uncertainty ( P = 95 %) ranged from 18.7 % (4:2 FTOH) to 38.7 % (10:2 FTOH), respectively.