Registration Dossier

Physical & Chemical properties

Vapour pressure

Currently viewing:

Administrative data

Link to relevant study record(s)

Reference
Endpoint:
vapour pressure
Type of information:
experimental study
Adequacy of study:
key study
Study period:
17 -27 Sept 2012
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: GLP -guideline study
Qualifier:
according to
Guideline:
OECD Guideline 104 (Vapour Pressure Curve)
Qualifier:
according to
Guideline:
other: OECD Guideline 113 (Screening test for thermal stability and stability in air)
Qualifier:
according to
Guideline:
EU Method A.4 (Vapour Pressure)
GLP compliance:
yes (incl. certificate)
Remarks:
Hessisches Ministerium für Umwelt, Energie, Landwirtschaft und Verbraucherschutz, Wiesbaden, Germany
Type of method:
effusion method: vapour pressure balance
Temp.:
20 °C
Vapour pressure:
0 hPa
Temp.:
25 °C
Vapour pressure:
0 hPa
Temp.:
50 °C
Vapour pressure:
0.003 hPa

The DSC-measurement in closed glass crucible with the test item showed multiple endothermic effects in the temperature range of 55 – 100 °C, 100 – 140 °C, 165 – 210 °C and 215 – 280 °C.

The vapour pressure was measured in the temperature range of 5 °C to 74 °C. Above 48 °C a vapour pressure could be measured. The measured vapour pressures at the corresponding temperatures are listed below:

Temperature / °C

Vapour pressure / hPa

47.6

1.9 × 10-4

50.2

1.4 × 10-3

52.8

3.2 × 10-3

55.7

4.6 × 10-3

58.8

6.1 × 10-3

62.2

7.7 × 10-3

64.6

9.3 × 10-3

67.2

1.0 × 10-2

70.4

1.3 × 10-2

74.0

1.6 × 10-2

The vapour pressure data showed an unusual behaviour with a two-staged curve shape. Only the values starting from 55 °C will be used for the evaluation as this yields more conservative results (for 20 °C, 25 °C and 50 °C). A molecular mass of 368.25 g/mol was used for this evaluation.

The vapour pressure (logarithmic scale) is evaluated as a function of the inverse temperature (1/T, T in Kelvin) for all values. Only for better readability the temperature is reported in a centigrade scale.

The values for 20, 25 and 50 °C are calculated, using the Antoine constants A, B and C. This result will be given as final result as it is more conservative.

Log (p/hPa) = A+B/(C+T/[°C]) with A=7.83417, B=-3339.21 and C=273.15

The following vapour pressure values for the test item were extrapolated from the experimental data:

Temperature / °C

Vapour pressure / hPa

Vapour pressure / Pa

20

2.8 × 10-4

2.8 × 10-2

25

4.3 × 10-4

4.3 × 10-2

50

3.2 × 10-3

3.2 × 10-1

 

Description of key information

0.00028 hPa at 20 °C
0.00043 hPa at 25 °C
0.0032 hPa at 50 °C (OECD 104)

Key value for chemical safety assessment

Vapour pressure:
0 hPa
at the temperature of:
20 °C

Additional information

The vapour pressure of the substance was determined by the effusion method (vapour pressure balance) according to OECD Guideline 104. The vapour pressure at 20, 25 and 50 °C was extrapolated from the vapour pressure curve.

The vapour pressure data showed an unusual behaviour with a two-staged curve shape. Only the values starting from 55 °C will be used for the evaluation as this yields more conservative results (for 20 °C, 25 °C and 50 °C) as a worst case scenario.