Registration Dossier

Administrative data

Endpoint:
vapour pressure
Type of information:
experimental study
Adequacy of study:
key study
Study period:
From 04 Dec 2013 to 10 July 2014
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: GLP study, OECD 104 compliant.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2014
Report Date:
2014

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
OECD Guideline 104 (Vapour Pressure Curve)
Qualifier:
according to
Guideline:
EU Method A.4 (Vapour Pressure)
GLP compliance:
yes (incl. certificate)
Remarks:
19 June 2013
Type of method:
effusion method: vapour pressure balance

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
solid: crystalline

Results and discussion

Vapour pressure
Remarks on result:
other: The vapour pressure of the test item could not be determined in an accurate way due to its high hygroscopic characteristic, a range of vapour pressure of the hydrated test item has been determined, from about 30 Pa to about 50 Pa between 20 °C and 30 °C.

Any other information on results incl. tables

The mass of sample weighed for each assay was reported in the table below. The sample was placed in a Knudsen effusion cell. Then the cell was placed in the apparatus.

For the assays No. 1, 4, 5 and 6, the test item was evaporated after the experimentations.

For the assays No. 2 and 3, the test was stopped before the test item was evaporated.

 

The vapour pressure of the test item was calculated by the “Knudsen software”. The calculation results are summarised in the following table:

Assay No.

Mass of test item
(mg)

Test temperature

t(°C)

Test temperature

T(K)

1/T(K-1)

Experimental vapour pressure P(Pa)

Log P

(Pa)

Knudsen effusion cell size(µm)

1

23.74

30.1

303.25

3.298 x 10-3

52.3

1.718

177.7

2

22.71

20.0

293.15

3.411 x 10-3

39.3

1.594

3

30.42

17.0

290.15

3.446 x 10-3

29.0

1.462

4

26.67

30.0

303.15

3.299 x 10-3

35.9

1.555

5

12.47

30.0

303.15

3.299 x 10-3

32.1

1.506

6

24.40

25.0

298.15

3.354 x 10-3

28.7

1.458

The first series with the assays No. 1, 2 and 3 were conducted with the test item weighed in standard conditions. The hydration of the test item was instantaneous during the weighing. The test item was completely liquid in the cell before placing it in the apparatus.

 

The second series with the assays No. 4, 5 and 6 were conducted with the test item weighed under dry nitrogen atmosphere with desiccant crystals. The hydration of the test item was reduced during the weighing but regarding the results, it seems that the test item was hydrated. The test item was partially liquid in the cell before placing it in the apparatus.

           

The results obtained with and without being under dry nitrogen atmosphere are slightly different. The vapour pressure is a little bit higher with the hydrated test item but the range of vapour pressure is similar.

 

Knowing that the expected vapour pressure for the dried test item is lower than the results obtained, these results show that it is quite impossible to determine the exact vapour pressure of the dried test item.

Applicant's summary and conclusion

Conclusions:
The vapour pressure of the test item could not be determined in an accurate way due to its high hygroscopic characteristic, a range of vapour pressure of the hydrated test item has been determined, from about 30 Pa to about 50 Pa between 20°C and 30°C.
Executive summary:

The objective of the study is to determine the vapour pressure of bis trifluoromethanesulfonimide, according to the OECD 104 guideline and under GLP conditions.

The method used was the Knudsen cell effusion method coupled to a micro-balance.

The vapour pressure of the test item could not be determined in an accurate way due to its high hygroscopic characteristic, a range of vapour pressure of the hydrated test item has been determined, from about 30 Pa to about 50 Pa between 20°C and 30°C.