Registration Dossier

Administrative data

Endpoint:
vapour pressure
Type of information:
experimental study
Adequacy of study:
key study
Study period:
February 23-24, 2016 (experimental phase)
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2016
Report Date:
2016

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
EU Method A.4 (Vapour Pressure)
Version / remarks:
European Commission Regulations (EC) No. 440/2008 and No. 761/2009, A.4. Vapour pressure: Effusion method
Deviations:
no
Qualifier:
according to
Guideline:
OECD Guideline 104 (Vapour Pressure Curve)
Deviations:
no
GLP compliance:
yes (incl. certificate)
Remarks:
Hess. Ministerium für Umwelt, Energie, Landwirtschaft und Verbraucherschutz, Mainzer Straße 80, D65189 Wiesbaden, Germany
Type of method:
effusion method: by loss of weight or by trapping vaporisate

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
solid: pellets
Details on test material:
- Substance type: pure substance
- Storage condition of test material: Ambient temperature (10 – 30 °C), protected from light

Results and discussion

Vapour pressureopen allclose all
Temp.:
50 °C
Vapour pressure:
0 hPa
Remarks on result:
other: measured
Temp.:
65 °C
Vapour pressure:
0 hPa
Remarks on result:
other: measured
Temp.:
80 °C
Vapour pressure:
0 hPa
Remarks on result:
other: measured
Temp.:
90 °C
Vapour pressure:
0 hPa
Remarks on result:
other: measured
Temp.:
100 °C
Vapour pressure:
0 hPa
Remarks on result:
other: measured
Temp.:
110
Vapour pressure:
0 hPa
Remarks on result:
other: measured
Temp.:
120 °C
Vapour pressure:
0 hPa
Remarks on result:
other: measured
Temp.:
20 °C
Vapour pressure:
0 hPa
Remarks on result:
other: Extrapolated. In the temperature range up to 80 °C intermediate vapour pressures up to approx. 3 × 10-5 hPa were detected which may be attributed to minor impurities.
Temp.:
25 °C
Vapour pressure:
0 hPa
Remarks on result:
other: Extrapolated. In the temperature range up to 80 °C intermediate vapour pressures up to approx. 3 × 10-5 hPa were detected which may be attributed to minor impurities.
Temp.:
50 °C
Vapour pressure:
0 hPa
Remarks on result:
other: Extrapolated. In the temperature range up to 80 °C intermediate vapour pressures up to approx. 3 × 10-5 hPa were detected which may be attributed to minor impurities.

Any other information on results incl. tables

Individual results

 

Vapour pressure balance

The vapour pressure was measured in the temperature range of 50 °C to 120 °C. For the calculation of the vapour pressure a molar mass of 648.1 g/mol was used based on the information provided by the study monitor. The measured vapour pressures at the corresponding temperatures are listed in Table 1.

 

Table1: Measured vapour pressures and corresponding temperatures

Temperature / °C

Vapour pressure / hPa

50

2.8×10-5

65

3.2×10-5

80

3.0×10-5

90

1.1×10-5

100

2.2×10-5

110

4.6×10-5

120

1.0×10-4

 

The data points measured at 50 °C, 65 °C and 90 °C showed a non-linear dependency between the vapour pressure (logarithmic scale) and the inverse temperature (1/T, T in Kelvin). This is a typical effect which can be attributed to minor impurities of higher vapour pressure than the main constituents.

The data points measured at 90 °C, 100 °C, 110 °C and 120 °C show a good linearity. After the measurement the test item was a solidified yellowish melt and the mass loss was found to be 3.3 %. Therefore, the data points measured at 90 °C and above are representative for the vapour pressure of the melted main constituents. Although the test item is a solid at room temperature it can be assumed that an extrapolation to room temperature is a valid approach to obtain conservative vapour pressure values for the main constituents.

Based on the data points measured at 90 °C and above a vapour pressure representative for the main constituents was calculated for 20 °C, 25 °C and 50 °C, using the Antoine constants A, B and C as shown in Table 2. Only for better readability the temperature is also reported in a centigrade scale.

 

Table2: Antoine parameters and extrapolated vapour pressures

T / °C

p / hPa

log (p/hPa) = A + B/(C+T[°C])

20

8.2×10-9*

A =

7.92627

25

1.5×10-8*

B =

-4694.62

50

2.5×10-7*

C =

273.15

*In the temperature range up to 80 °C intermediate vapour pressures up to approx. 3×10-5 hPa were detected which may be attributed to minor impurities.

 

Final results

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

 

T / °C

p / hPa

p / Pa

20

8.2×10-9*

8.2×10-7*

25

1.5×10-8*

1.5×10-6*

50

2.5×10-7*

2.5×10-5*

*In the temperature range up to 50 °C intermediate vapour pressures up to approx. 3×10-5 hPa were detected which may be attributed to minor impurities.

Applicant's summary and conclusion

Conclusions:
The vapor pressure was determined in a GLP guideline study according to OECD 104, and EU method A.4 without deviations on the registered substance itself. Hence, there is no indication given that the results are not reliable.
Vapour pressure values were extrapolated from the experimental data to 8.2 × 10-7 Pa at 20°C, 1.5 × 10-6 Pa at 25°C, and 2.5 × 10-5 Pa at 50°C.
Executive summary:

The vapor pressure of Octadecanoic acid, reaction products with tetraethylenepentamine was determined in a GLP guideline study according to OECD 104 and EU method A.4. Vapour pressure values were extrapolated from the experimental data to 8.2×10-7 Pa at 20°C, 1.5×10-6 Pa at 25°C, and 2.5×10-5 Pa at 50°C.