Registration Dossier

Physical & Chemical properties

Vapour pressure

Currently viewing:

Administrative data

Link to relevant study record(s)

Referenceopen allclose all

Endpoint:
vapour pressure
Type of information:
experimental study
Adequacy of study:
key study
Study period:
2010-04-21
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study
Reference:
Composition 1
Qualifier:
according to
Guideline:
EU Method A.4 (Vapour Pressure)
GLP compliance:
no
Type of method:
dynamic method
Test material information:
Composition 1
Temp.:
25 °C
Vapour pressure:
0.007 Pa
Remarks on result:
other: extrapolated value
Temp.:
189 °C
Vapour pressure:
11 mBar
Temp.:
226.5 °C
Vapour pressure:
63 mBar

Multiple data-points were recorded between 63 and 11mBar and 226.5 and 189.0°C respectively, to generate a graph to allow vapour pressure determination at 25°C.

Vapour Pressure Data - ASG:10423676

Pressure (mBar)

Temperature (°C)

Temperature (K)

1/T

Ln P

63

226.5

499.7

0.002001401

4.143134726

49

222.8

496.0

0.002016332

3.891820298

46

223

496.2

0.00201552

3.828641396

37

219.6

492.8

0.002029427

3.610917913

31

215.1

488.3

0.002048131

3.433987204

22

205.4

478.6

0.002089646

3.091042453

11

189

462.2

0.0021638

2.397895273

31

215

488.2

0.002048551

3.433987204

45

223.5

496.7

0.00201349

3.80666249

Vapour Pressure at 25°C

1/T

Ln P

P (mBar)

P (Pa)

0.003354016

-9.6292160

0.00006577860

0.006578

 

Conclusions:
The vapour pressure of the test substance was 0.0066 Pa at 25°C.
Executive summary:

The vapour pressure of the test substance was determined using an Ebulliometer (LIMS:1833, PQ Done:11/03/10, PQ Due:11/09/10) in accordance with EU guideline A.4. The value extrapolated to 25°C was 0.0066 Pa.

The sample gave a colour change during the experiment; therefore, it is possible that sample degradation had occurred.  Sample 10423676 gave acceptable data, however, extrapolation of data was required to give vapour pressure data at 25°C and as such, the vapour pressure value reported is outside of the recommended range of the technique and this will affect the accuracy of the determination. Further assessment of the vapour pressure may be possible, if required, using the Gas Saturation Method to allow a more accurate value to be given.

Endpoint:
vapour pressure
Type of information:
experimental study
Adequacy of study:
supporting study
Study period:
1999-02-12
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
guideline study
Reference:
Composition 1
Qualifier:
according to
Guideline:
EU Method A.4 (Vapour Pressure)
Deviations:
not specified
GLP compliance:
yes
Type of method:
effusion method: vapour pressure balance
Test material information:
Composition 1
Temp.:
20 °C
Vapour pressure:
0 hPa
Temp.:
25 °C
Vapour pressure:
0 hPa
Temp.:
28.5 °C
Vapour pressure:
0 hPa
Temp.:
50 °C
Vapour pressure:
0 hPa

This method is most appropriate for the evaluation of vapour pressure values ranging from 10^-4 to 10^-2 hPa. The method is not suitable for vapour pressure values above 10^-2 hPa.

Values that deviated significantly from the regression curve were not included in the analysis for the following reasons:

 For values significantly too high:

Annealing effects (typical of the first measuring cycle) or substance condensation on the oven cap simulate an increased density of vapour stream.

For values significartly too low:

Substance condensation at the orifice or the oven exhaust duct reduces the cross section of the vapour stream.

Conclusions:
The vapour pressure of test substance ranged from 7.7 x 10^-6 to 2.3 x 10^-4 hPa, for temperatures ranging from 20°C to 50°C.
Executive summary:

The vapour pressure of test substance was measured using the vapour pressure balance method according to the current EU guideline A4. The vapour pressure values obtained for temperatures ranging from 20°C to 50°C were in the range of 7.7 x 10^-6 to 2.3 x 10^-4 hPa.

Endpoint:
vapour pressure
Type of information:
experimental study
Adequacy of study:
supporting study
Study period:
1999-02-12
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study
Reference:
Composition 1
Qualifier:
according to
Guideline:
EU Method A.4 (Vapour Pressure)
Deviations:
not specified
GLP compliance:
yes
Type of method:
dynamic method
Test material information:
Composition 1
Temp.:
150 °C
Vapour pressure:
1.1 hPa
Temp.:
200 °C
Vapour pressure:
11.2 hPa
Temp.:
250 °C
Vapour pressure:
77 hPa

This method is most suitable for the evaluation of compounds having a vapour pressure of 1 to 1000 hPa. The most suitable temperature range is 20°C to 250°C.

Conclusions:
The vapour pressure of test substance was found to be 1.1, 11.2, and 77.0 hPa for temperatures of 150°C, 200°C, and 250°C, respectively.
Executive summary:

The vapour pressure of test substance was measured using the dynamic method according to the current EU guidedline A.4. Vapour pressure values of 1.1, 11.2, and 77.0 hPa were obtained at temperatures of 150°C, 200°C, and 250°C, respectively.

Description of key information

The vapour pressure of Isopentyl p-methoxycinnamate was 0.0066 Pa at 25°C. 

Key value for chemical safety assessment

Vapour pressure:
0.007 Pa
at the temperature of:
25 °C

Additional information

The vapour pressure of test substance was measured in 3 studies. All three studies were performed according to the current EU method A4.

In one of these studies, the vapour pressure balance method was used, whereas the dynamic method was used in the 2 other studies.

In the key study using the dynamic method, vapour pressure values ranging from 11 to 63 mbar (corresponds to hPa) were observed for temperatures ranging from 189.0°C to 226.5°C. The vapour pressure extrapolated at a temperature of 25°C is 0.0066 Pa. In the second study using this method, vapour pressure values of 1.1, 11.2, and 77.0 hPa were obtained at temperatures of 150°C, 200°C, and 250°C, respectively. Both results are scientifically reliable and fall within the same range. As the extrapolated value at 25°C was not given in the second study report, the first study using dynamic method was used as the key study, whereas the second study using this method is used as a supporting study. With the vapour pressure balance method, values in the range of 7.7 x 10-6 to 2.3 x 10-4 hPa were obtained for temperatures ranging from 20°C to 50°C which is in the same range as the values obtained with the dymanic method. Nevertheless, the lowest value of 7.7 x 10-6 hPa is below the limit of this method (10-4hPa).

Therefore the result is less reliable and used as a supporting study.