Registration Dossier

Data platform availability banner - registered substances factsheets

Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.

The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.

Diss Factsheets

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:
02.03.2018 - 09.05.2018
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study
Qualifier:
according to guideline
Guideline:
OECD Guideline 104 (Vapour Pressure Curve)
Version / remarks:
2006
Deviations:
no
GLP compliance:
no
Type of method:
effusion method: Knudsen cell
Key result
Test no.:
#1
Temp.:
20 °C
Vapour pressure:
0.002 Pa
Key result
Test no.:
#2
Temp.:
25 °C
Vapour pressure:
0.004 Pa
Key result
Test no.:
#3
Temp.:
50 °C
Vapour pressure:
0.074 Pa

Thermal Stability

In the temperature range of 120 °C – 140 °C the test item showed an endothermic effect, which can be assigned to the melting of the test item. An exothermic effect was observed in the temperature of 340 °C – 410 °C with a decomposition energy of -110 J/g. No further thermal effects could be observed up to the maximum test temperature of 500 °C.

Table 1:    Results of the DSC-measurement

No.

Sample weight / mg

Start / °C

Energy / J/g

Remark

PN15087

9.57

120 (endothermic)
340 (exothermic)

+170
-110

Figure 2

Effusion method: Knudsen cell

The vapour pressure was measured in the temperature range of 30.4 °C to 50.7 °C. The measured vapour pressure values together with the measured temperatures are listed in Table 2:

Table 2:    Results of the Effusion method

No.

Temperature / °C

Vapour pressure / Pa

1

30.4

7.6 × 10-3

2

35.5

1.4 × 10-2

3

40.6

2.6 × 10-2

4

45.6

4.5 × 10-2

5

50.7

8.0 × 10-2

From the measured data points of the vapour pressure curve the constants A and B of the Antoine Equation were derived by regression of the data points to A = 14.2703, B = -4976.48, C = 273.15.

The vapour pressure of the test item Methylhydroquinone calculated by interpolation and extrapolation of the measured vapour pressure curve for the temperatures 20 °C, 25 °C and 50 °C, according to Regulation EC No. 440/2008 Method A.4.Vapour Pressure and OECD Test Guideline 104 (2006) is shown in Table 3:

Table 3:    Calculated vapour pressure values for 20 °C, 25 °C and 50 °C

Temperature / °C

Vapour pressure / Pa

20

2.0 × 10-3

25

3.8 × 10-3

50

7.4 × 10-2
Conclusions:
The vapor pressure of methylhydroquinone at 20°C, 25°C and 50°C is 0,002 Pa, 0,0038 Pa and 0,074 Pa, respectively.
Executive summary:

The vapour pressure of the test item Methylhydroquinone was calculated by interpolation and extrapolation of the measured vapour pressure curve for the temperatures 20 °C, 25 °C and 50 °C, according to Regulation EC No. 440/2008 Method A.4. Vapour Pressure and OECD Test Guideline 104 (2006).

Temperature / °C

Vapour pressure / Pa

20

2.0 × 10-3

25

3.8 × 10-3

50

7.4 × 10-2

Description of key information

The vapor pressure of methylhydroquinone at 20°C is 0,002 Pa, at 25°C 0,0038 Pa and at 50°C 0,074 Pa as determined by the effusion method (Knudsen cell).

Key value for chemical safety assessment

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

Additional information