Disodium 3,3'-[[6-[bis(2-hydroxyethyl)amino]-1,3,5-triazine-2,4-diyl]bis[imino(3-methoxy-4,1-phenylene)azo]]bis[benzenesulphonate]

Vapour pressure

Link to relevant study record(s)

Reference

Endpoint:

vapour pressure

Type of information:

experimental study

Adequacy of study:

key study

Study period:

July from 19 to 21, 2017

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

test procedure in accordance with generally accepted scientific standards and described in sufficient detail

Qualifier:

according to guideline

Guideline:

OECD Guideline 104 (Vapour Pressure Curve)

Version / remarks:

2006

Qualifier:

according to guideline

Guideline:

other: OECD Test Guideline 113

Version / remarks:

1981

Qualifier:

according to guideline

Guideline:

EU Method A.4 (Vapour Pressure)

Qualifier:

according to guideline

Guideline:

EPA OPPTS 830.7950 (Vapor Pressure)

Version / remarks:

1996

GLP compliance:

yes (incl. QA statement)

Type of method:

effusion method: vapour pressure balance

Test no.:

#1

Temp.:

20 °C

Vapour pressure:

0 Pa

Test no.:

#2

Temp.:

25 °C

Vapour pressure:

0 Pa

Test no.:

#3

Temp.:

50 °C

Vapour pressure:

0 Pa

THERMAL STABILITY

The test item shows a first exothermic effect from 220 °C with an average energy release of -20 J/g. An endothermic effect is detected from 240 °C. This effect leads into an exothermic effect, starting from 260 °C with an average energy release of -350 J/g.

Result of DSC-measurements

No.	Sample weight (mg)	Start of effect (°C)	Energy (J/g)
PN13874	7.43	220	-10
		240	20
		260	-320
PN13875	7.32	220	-20
		240	20
		260	-380

EFFUSION METHOD: VAPOUR PRESSURE BALANCE

The vapour pressure was measured in the temperature range of 148 to 183 °C.

Result of effusion method

No.	Temperature (°C)	Vapour pressure (Pa)
1	148	2.37 × 10^-3
2	158	2.68 × 10^-3
3	168	4.52 × 10^-3
4	173	5.60 × 10^-3
5	178	7.49 × 10^-3
6	183	1.02 × 10^-2

The measured vapour pressures no. 1 and 2 are slightly outside the measuring range (10^-3 to 1 Pa) of the Knudsen cell. Nevertheless, as the vapour pressure values below 10^-3 Pa could be detected properly by the Knudsen cell, these values can be used for the evaluation.

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

Calculated vapour pressure

Temperature (°C)	Vapour pressure (Pa)
20	3.2 × 10^-8
25	5.8 × 10^-8
50	8.6 × 10^-7

Conclusions:

Vapour pressure: 3.2 × 10-8 Pa at 20 °C, 5.8 × 10-8 Pa at 25 °C, 8.6 × 10-7 Pa at 50 °C

Executive summary:

Before performing the test to determine the vapour pressure of a test item a DSC-measurement in a closed glass crucible under nitrogen will be performed up to a temperature of 500 °C to determine the thermal stability of the test item. The vapour pressure was measured in the temperature range of 148 to 183 °C with the vapour pressure balance method, by which can be measured values in the temperature range 15 to 150 °C and in the pressure range 10 ^-3 to 1 Pa. The measured vapour pressures vales resulted to be slightly outside the measuring range of the Knudsen cell. Thus, the vapour pressure of the test item was calculated by extrapolation of the measured vapour pressure curve for the temperatures 20, 25 and 50 °C, according to Regulation EC No. 440/2008 Method A.4. Vapour Pressure and OECD Test Guideline No. 104 (2006).

Conclusion

3.2 × 10^-8 Pa at 20 °C

5.8 × 10^-8 Pa at 25 °C

8.6 × 10^-7 Pa at 50 °C

Description of key information

Negligible

Key value for chemical safety assessment

Vapour pressure:

0 Pa

at the temperature of:

20 °C

Additional information

Based on DSC analysis, the substance undergoes to decomposition before melting/boiling. The vapour pressure was in any case calculated by extrapolation of the measured vapour pressure curve.