Reaction mass of hydrogen [1-[(2-hydroxy-4-nitrophenyl)azo]-2-naphtholato(2-)][1-[(2-hydroxy-5-nitrophenyl)azo]-2-naphtholato(2-)]chromate(1-) , compound with 3-[(2-ethylhexyl)oxy]propylamine (1:1) and hydrogen bis[1-[(2-hydroxy-4-nitrophenyl)azo]-2-naphtholato(2-)]chromate(1-) , compound with 3-[(2-ethylhexyl)oxy]propylamine (1:1) and hydrogen bis[1-[(2-hydroxy-5-nitrophenyl)azo]-2-naphtholato(2-)]chromate(1-) , compound with 3-[(2-ethylhexyl)oxy]propylamine (1:1)

Vapour pressure

Link to relevant study record(s)

Reference

Endpoint:

vapour pressure

Type of information:

experimental study

Adequacy of study:

key study

Study period:

25 August 2017 to 29 August 2017

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

Qualifier:

according to guideline

Guideline:

EU Method A.4 (Vapour Pressure)

Version / remarks:

2009

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

effusion method: isothermal thermogravimetry

Key result

Test no.:

#1

Temp.:

20 °C

Vapour pressure:

0 Pa

- According to EU Safety Data Sheet the melting point for the test material is >300 °C. The evaluation of the vapour pressure could be performed only with the reproducible weight loss values above ≥ 1 μg/min and in this case was performed with the results above 220 °C and thus below the melting point.

- The results of the isothermal TGA analysis are given in Table 1.

Table 1: Weight loss of the test item in the temperature range of 220 to 250 °C

Temperature (°C)	1/T (K)	1000/T (K)	Weight loss (µg/min)	VT (g/cm^2h)	log VT
220	0.00203	2.02840	40.33	0.004840	-2.315191
220	0.00203	2.02840	37.06	0.004447	-2.351913
220	0.00203	2.02840	34.41	0.004129	-2.384134
230	0.00199	1.98807	53.37	0.006404	-2.193522
230	0.00199	1.98807	56.81	0.006817	-2.166394
230	0.00199	1.98807	50.90	0.006108	-2.214101
240	0.00195	1.94932	78.53	0.009424	-2.025783
240	0.00195	1.94932	81.05	0.009726	-2.012066
240	0.00195	1.94932	78.49	0.009419	-2.026004
250	0.00191	1.91205	118.6	0.014232	-1.846734
250	0.00191	1.91205	120.0	0.014400	-1.841638
250	0.00191	1.91205	105.0	0.012600	-1.899629

Estimation of VT and PT:

log VT at 20 °C: -8.1840246

log PT at 20 °C: -4.5007613

PT at 20 °C: 0.0000316

PT (Pa) at 20 °C: 3.16E-05

- The coefficient of correlation (R^2) was 0.9854. The resulting equation was:

log PT = 4.7300 + 1.1279 · log VT

Inserting the equation for log VT above, the following equation for the temperature dependence of the vapour pressure of the test material is obtained:

log PT = C+D · (a · (1000/T) +b) = C+(D · b)+(D · a · 1000 )/T

(where: a = -4.2103, b = 6.1856, C = 4.7300 and D = 1.1279)

With this equation, a following vapour pressure results were obtained: 3.16 × 10^-5 Pa at 20 °C.

Conclusions:

Under the conditions of this study, the vapour pressure of the test material was calculated (mean of three determinations) to be 3.16 × 10^-5 Pa at 20 °C.

Executive summary:

The vapour pressure of the test material was investigated in accordance with the standardised guidelines OECD 104 and EU Method A.4, under GLP conditions.

The vapour pressure was determined using the isothermal thermogravimetric effusion method. According to EU Safety Data Sheet the melting point for the test material is >300 °C. The evaluation of the vapour pressure could be performed only with the reproducible weight loss values above ≥ 1 μg/min and in this case was performed with the results above 220 °C and thus below the melting point.

A value of the vapour pressure of the test material was determined using the data obtained between 190 and 250 °C.

Under the conditions of this study, the vapour pressure of the test material was calculated (mean of three determinations) to: 3.16 × 10 ^-5 Pa at 20 °C.

Description of key information

A value of the vapour pressure of the test material was determined using the data obtained between 190 and 250 °C.

Under the conditions of this study, the vapour pressure of the test material was calculated (mean of three determinations) to: 3.16 × 10^-5 Pa at 20 °C.

Key value for chemical safety assessment

Vapour pressure:

0 Pa

at the temperature of:

20 °C

Additional information

The vapour pressure of the test material was investigated in accordance with the standardised guidelines OECD 104 and EU Method A.4, under GLP conditions. The study was awarded a reliability score of 1 in accordance with the criteria set forth by Klimisch et al. (1997).

The vapour pressure was determined using the isothermal thermogravimetric effusion method. According to EU Safety Data Sheet the melting point for the test material is >300 °C. The evaluation of the vapour pressure could be performed only with the reproducible weight loss values above ≥ 1 μg/min and in this case was performed with the results above 220 °C and thus below the melting point.

A value of the vapour pressure of the test material was determined using the data obtained between 190 and 250 °C.

Under the conditions of this study, the vapour pressure of the test material was calculated (mean of three determinations) to: 3.16 × 10^-5 Pa at 20 °C.