3-ethoxy-1,1,1,2,3,4,4,5,5,6,6,6-dodecafluoro-2-(trifluoromethyl)-hexane

Boiling point

Description of key information

Key result for CAS# 297730-93-9:
Boiling point at 760 mm Hg: 129°C (DSC per OECD TG103)
Key result for PFBA (degradation product), CAS# 375-22-4:
Boiling point at 101 kPa (760 mmHg): 121.8 °C (dual ebulliometer technique equivalent to OECD103)

Additional information

Discussion for CAS# 297730-93-9:

Boiling temperature of CAS# 297730-93-9 was reported in four studies. The key study used differential scanning calorimetry according to OECD TG103 to measure a boiling temperature of 129 °C. The pressure during the experiment was not reported, however given experimental conditions the result is accurate within a limit of ±1.7 °C. The three supporting studies generally corroborate this value. In the second of the four studies, vapor pressure (VP) of CAS# 297730-93-9 was determined over temperatures from 30 °C to 130 °C using dynamic ebulliometry according to ASTM methods E1719-97 and D1120-94.  VP data was then fit to the Antoine equation. The parameterized equation was then used to extrapolate a boiling temperature of 130.2 °C at 760 mmHg. The third and fourth values were summary data points obtained from scientific literature. The values reported were 128 °C and 123.5 °C, respectively. The reports specify neither the methods used to obtain these temperatures nor the pressures at which the measurements were obtained.

 

The key study was performed according to internationally accepted test guidelines and GLP criteria. While pressure was not reported, the test gives an estimated correction factor of 0.33 K/kPa at 398.15K, which is valid for ambient barometric pressures of 101.35±5 kPa (760±38 mm Hg). The maximum valid correction is 1.7 K. Since the study was performed at a low elevation, it is unlikely that ambient barometric pressure during the test was outside of the acceptable range, and the actual boiling point is within the limit of ±1.7°C. The second study was conducted using a mixture of ASTM test methods but GLP standards were not cited. These two studies are therefore classified as reliable with restrictions. The two remaining studies are literature reports that cannot be classified as to reliability. The third study supports the key study, while the fourth study contradicts the key study. Since the validity of the fourth study cannot be assessed, the reported value is not given further consideration.

Discussion for PFBA (degradation product), CAS# 375-22-4:

The boiling point of PFBA was determined by interpolation of vapor pressures measured using a dual ebulliometer technique as part a large scale effort to accurately and precisely determine thermodynamic characteristics of a variety of industrially-important chemicals. The methods used are equivalent to OECD103. The result has been compiled into peer-reviewed chemical information databases such as Beilstein, and the extrapolation is classified as reliable with restrictions. An additional boiling temperature was reported at 98 kPa (735 mm Hg) but is not considered further due to non-standard pressure.