N, N-bis-(2-hydroxyethyl) dimethyl ammonium methane sulfonate

Vapour pressure

Link to relevant study record(s)

Reference

Endpoint:

vapour pressure

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Study initiation: 2021-03-16;
Experimental completion date: 2021-03-24

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:

European Commission Regulations (EC) No. 440/2008 and No. 761/2009

Deviations:

no

Qualifier:

according to guideline

Guideline:

OECD Guideline 104 (Vapour Pressure Curve)

Version / remarks:

2006

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

effusion method: Knudsen cell

Key result

Temp.:

20 °C

Vapour pressure:

0.002 Pa

Remarks on result:

other: Extrapolated from Antoine equation

Details on measurements:

The vapour pressure was measured in the temperature range of 30 °C to 110 °C. The measured vapour pressures at the corresponding temperatures are listed in Table 1. After the measurement the test item appeared unchanged and a mass loss of approx. 0.4 % (w/w) was determined.

Table 1: Measured vapour pressures and corresponding temperatures

Temperature / °C	Vapour pressure / hPa
30	2.5 × 10^-5
35	2.0× 10^-5
40	2.2 × 10^-5
50	2.7 × 10^-5
60	3.4 × 10^-5
70	3.7× 10^-5
80	3.8× 10^-5
90	4.2× 10^-5
100	4.4× 10^-5
110	5.9 × 10^-5

The data point measured at 30 °C was not included in the linear regression because it showed a typical deviation caused by volatile impurities at the beginning of a measurement.

Figure 1 on given in the illustration attached to this endpoint study record gives the vapour pressure (logarithmic scale) as a function of the inverse temperature (1/T, T in Kelvin). Only for better readability the temperature is also reported in a centigrade scale.

From the measured data the parameters A, B and C of the Antoine equation can be derived by regression.

log (p [hPa]) = A + B/(C + T [°C])

Antoine parameters

A	-2.567
B	-649.6
C	273.15

The vapour pressure values for 20, 25 and 50 °C were extrapolated (values at 20 °C and 25 °C) and interpolated (value at 50 °C), using these Antoine constants A, B and C. The coefficient of determination R² was determined to be 0.955.

Vapour pressures (as calculated from Antoine equation):

T / °C	p / hPa	p / Pa
20	1.7 × 10^-5	1.7 × 10^-3
25	1.8 × 10^-5	1.8 × 10^-3
50	2.6 × 10^-5	2.6 × 10^-3

Conclusions:

Vapour pressure at 20 °C (OECD 104; A.4; effusion method): 1.7E-3 Pa

Executive summary:

The vapour pressure of the test item was determined in a reliable and valid study performed compliant with GLP according to OECD 104 as well as EU method A.4. (Vapour pressure: effusion method). The method was chosen due to its high sensitivity and the fact that the test item is an ionic liquid and thus of low vapour pressure.
The vapour pressure was measured in the temperature range of 30 °C to 110 °C. From the experimental results, Antoine constants were derived by regression analysis (coefficient of determination R^2 was determined to be 0.955).

The following vapour pressure values for the test item MAT-144 were extrapolated (values at 20 °C and 25 °C) and interpolated (value at 50 °C) from the experimental data using the Antoine equation:

Vapour pressure at 20 °C: 1.7E-3 Pa;
Vapour pressure at 25 °C: 1.8E-3 Pa;
Vapour pressure at 50 °C: 2.6E-3 Pa.

Description of key information

Vapour pressure at 20 °C (OECD 104; A.4; effusion method): 1.7E-3 Pa

Key value for chemical safety assessment

Vapour pressure:

0.002 Pa

at the temperature of:

20 °C

Additional information

The vapour pressure of the test item was determined in a reliable and valid study performed compliant with GLP according to OECD 104 as well as EU method A.4. (Vapour pressure: effusion method). The method was chosen due to its high sensitivity and the fact that the test item is an ionic liquid and thus of low vapour pressure.
The vapour pressure was measured in the temperature range of 30 °C to 110 °C. From the experimental results, Antoine constans were derived by regression analysis (coefficient of determination R^2 was determined to be 0.955).

The following vapour pressure values for the test item MAT-144 were extrapolated (values at 20 °C and 25 °C) and interpolated (value at 50 °C) from the experimental data using the Antoine equation:

Vapour pressure at 20 °C: 1.7E-3 Pa;
Vapour pressure at 25 °C: 1.8E-3 Pa;
Vapour pressure at 50 °C: 2.6E-3 Pa.