α,α,α-trifluoro-4-nitro-m-cresol

Vapour pressure

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

vapour pressure

Type of information:

experimental study

Adequacy of study:

key study

Study period:

from 1999-04-30 to 1999-06-23

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

EU Method A.4 (Vapour Pressure)

Version / remarks:

92/69/EEC of 31 July 1992

Deviations:

no

GLP compliance:

yes

Type of method:

effusion method: vapour pressure balance

Specific details on test material used for the study:

Batch No.: 13111BR
Purity: 99.3 %

Key result

Temp.:

20 °C

Vapour pressure:

0 hPa

Key result

Temp.:

25 °C

Vapour pressure:

0 hPa

Temp.:

50 °C

Vapour pressure:

0 hPa

As a precaution a DSC was performed. The measurement in a closed glass pan showed an endothermal effect (melting) at 73 °C and an exothermal decomposition beginning at 250 °C.

The vapour pressure was measured in the temperature range of 20 to 89 °C. No signal was observed in the range 20 to 69 °C, that means the vapour pressure in this range was below 1E-05 hPa. Above this temperature a vapour pressure could be measured.

Measured data:

Temperature (°C)	Vapour Pressure (hPa)
69.0	3.0 x 10^-3
74.8	5.2 x 10^-3
78.3	9.9 x 10^-3
79.1	3.6 x 10^-2
82.8	5.9 x 10^-2
83.3	9.0 x 10^-2
87.1	1.9 x 10^-1
89.2	3.3 x 10^-1

The values above 79.1 °C were outside the recommended range of max 1E-02 hPa. But this is tolerable because the shutter opening time of the vapour pressure balance was shortened from regular 60 sec, to 40, 30 and 20 seconds.

The fitted Antoine-equation yielded an extrapolated vapour pressure at 50 °C of 8.81E-08 hPa.

The extrapolated vapour pressure for 25 °C was 2.75E-09 hPa.

Conclusions:

The vapour pressure of the test substance at 20 °C was extrapolated from the measured vapour pressure at higher temperature. It was extrapolated to be 4.64E-10 hPa.

Executive summary:

A study was conducted according to Regulation (EC) No 92/69/EEC method A.4 to determine the vapour pressure of the test item. The vapour pressure of the test item was determined at temperatures from 20 to 89 °C using the effusion method (vapour pressure balance). In the range 20 to 69 °C no vapour pressure could be measured, which showed that the vapour pressure of the test substance in this temperature range is below the limit of the method - 1E-05 hPa. Therefore, the vapour pressure of the test substance was determined in the temperature range of 69 to 89 °C. The vapour pressure was calculated using the linear regression equation of the Log P versus 1/T function. The vapour pressure was calculated to be 4.64E-10 hPa at 20 °C, 2.75E-09 hPa at 25 °C and 8.81E-06 hPa at 50 °C, respectively.

Reference 2

Endpoint:

vapour pressure

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

1989-06-19

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

test procedure in accordance with national standard methods with acceptable restrictions

Qualifier:

no guideline followed

Principles of method if other than guideline:

measured (not specified)

GLP compliance:

not specified

Type of method:

dynamic method

Specific details on test material used for the study:

Purity: 36 % active ingredient in formulation product

Temp.:

20 °C

Vapour pressure:

30.6 mBar

Key result

Temp.:

20 °C

Vapour pressure:

30.6 hPa

Temp.:

25 °C

Vapour pressure:

44.1 hPa

Temp.:

50 °C

Vapour pressure:

193.1 mBar

Temp.:

50 °C

Vapour pressure:

193.1 hPa

Measured Calibration Curve of the test item

Temperature (°C)	Vapour Pressure – measured (hPa)	Vapour Pressure – calculated (hPa)	Standard deviation (%)
23.7	40.3	40.2	0.3
34.3	80.4	81.0	-0.8
45.0	150.2	149.3	0.6
59.4	300.7	300.9	-0.1
71.6	499.7	499.9	-0.0

 

Calculated Vapour Pressure and Heat LP

Temperature (°C)	Vapour Pressure (hPa)	Vapour Pressure (Torr)	Heat LP (kJ/mol)
0.0	5.2	3.9	65.2
10.0	13.5	10.2	58.9
20.0	30.6	23.0	53.9
25.0	44.1	33.0	51.7
30.0	61.7	46.3	49.7
40.0	113.4	85.1	46.3
50.0	193.1	144.9	43.4
60.0	309.1	231.8	40.9
70.0	469.6	352.2	38.7
80.0	682.8	512.2	36.8
90.0	956.6	717.5	35.1

 

Conclusions:

The vapour pressure of the test substance at 20 °C was determined to be 30.6 mbar or 30.6 hPa.

Executive summary:

The vapour pressure of the test substance was determined using the dynamic method. It was determined to be 30.6 mbar or 30.6 hPa at 20 °C, and 193.1 mabr or 193.1 hPa at 50 °C, respectively.

Description of key information

The vapour pressure of the test substance at 20 °C was extrapolated from the measured vapour pressure at higher temperature. It was extrapolated to be 4.64E-10 hPa.

Key value for chemical safety assessment

Vapour pressure:

0 hPa

at the temperature of:

20 °C

Additional information

Key study

A study was conducted according to Regulation (EC) No 92/69/EEC method A.4 to determine the vapour pressure of the test item. The vapour pressure of the test item was determined at temperatures from 20 to 89 °C using the effusion method (vapour pressure balance). In the range 20 to 69 °C no vapour pressure could be measured, which showed that the vapour pressure of the test substance in this temperature range is below the limit of the method - 1E-05 hPa. Therefore, the vapour pressure of the test substance was determined in the temperature range of 69 to 89 °C. The vapour pressure was calculated using the linear regression equation of the Log P versus 1/T function. The vapour pressure was calculated to be 4.64E-10 hPa at 20 °C, 2.75E-09 hPa at 25 °C and 8.81E-06 hPa at 50 °C, respectively.

Supporting study

In a supporting study, the vapour pressure of a formulation, containing 36 % of test substance, was determined be 30.6 mbar or 30.6 hPa at 20 °C.