2-methylpentyl 2-hydroxybenzoate

Vapour pressure

Link to relevant study record(s)

Reference

Endpoint:

vapour pressure

Type of information:

experimental study

Adequacy of study:

key study

Study period:

18-03-2020 to 13-05-2020

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

Guideline study performed under GLP. All relevant validity criteria were met.

Qualifier:

according to guideline

Guideline:

EU Method A.4 (Vapour Pressure)

Deviations:

no

Qualifier:

according to guideline

Guideline:

OECD Guideline 104 (Vapour Pressure Curve)

Deviations:

no

Qualifier:

equivalent or similar to guideline

Guideline:

EPA OPPTS 830.7950 (Vapor Pressure)

Deviations:

no

GLP compliance:

yes

Type of method:

effusion method: isothermal thermogravimetry

Key result

Test no.:

#1

Temp.:

20 °C

Vapour pressure:

0.28 Pa

Key result

Test no.:

#1

Temp.:

25 °C

Vapour pressure:

0.47 Pa

The results of the isothermal TGA analysis for the test item and the vapour pressure at 20°C and 25°C are given in the following tables.

 

Table 2 Results of the isothermal TGA analysis

	Temperature [°C]	Weight loss [µg/min]	νT [g/cm2/h]	logνT	log PT	PT [Pa]
1	30	0.541291	6.46 x 10^-5	-4.19	-0.09	0.82
	40	1.30379	1.56 x 10^-4	-3.81	0.34	2.2
	50	2.37094	2.83 x 10^-4	-3.55	0.63	4.3
	60	6.59099	7.87 x 10^-4	-3.10	1.13	14
2 #	30	0.365112	4.36 x 10^-5	-4.36	-0.28	0.53
	40	0.496859	5.93 x 10^-5	-4.23	-0.13	0.74
	50	1.80332	2.15 x 10^-4	-3.67	0.50	3.2
	60	4.33313	5.17 x 10^-4	-3.29	0.93	8.5
3	30	0.563481	6.73 x 10^-5	-4.17	-0.07	0.86
	40	1.20627	1.44 x 10^-4	-3.84	0.30	2.0
	50	3.04095	3.63 x 10^-4	-3.44	0.75	5.7
	60	7.06792	8.44 x 10^-4	-3.07	1.17	15

# Experiment 2: excluded from calculation

 

The vapour pressure regression curve constructed using the data of Experiment 1 and Experiment 2 had a coefficient of correlation of <0.99. Therefore, a third experiment was performed to calculate the coefficient of correlation for Experiment 1 + Experiment 2 + Experiment 3, for Experiment 1 + Experiment 3 and for Experiment 2 + Experiment 3. A coefficient of correlation was obtained >0.99 only for the combination of Experiment 1+ Experiment 3. Therefore the results from Experiment 2 were excluded from further analysis. The plot of the log PT of the test item as function of the reciprocal temperatures was performed. The equation of the curve was: log PT,20 = -4087 × 1/T + 13.38 (r = 0.995, n = 8).

 

Table 2 Vapour pressure of the test item

Temperature [°C]	log PT	PT [Pa]	PT [mm Hg]
20	-0.56	0.28	2.1 x 10^-3
25	-0.32	0.47	3.6 x 10^-3

Conclusions:

The vapour pressure of the test item was determined to be 0.28 Pa at 20°C and 0.47 Pa at 25°C, respectively.

Executive summary:

The vapour pressure was determined according to EU Method A.4 and OECD TG 104 using the thermogravimetric effusion method under GLP. The vapour pressure regression curve constructed using the data of Experiment 1 and Experiment 3 since coefficient of correlation was obtained at >0.99 only for this combination. The results from Experiment 2 were excluded from further analysis. The plot of the log PT of the test item as function of the reciprocal temperatures was performed. The equation of the curve was: log PT,20 = -4087 × 1/T + 13.38 (r = 0.995, n = 8). The vapour pressure of the test item was determined to be 0.28 Pa (or 2.1 x 10^-3 mm Hg) at 20°C, and 0.47 Pa (or 3.6 x 10^-3 mm Hg) at 25°C.

Description of key information

Vapour Pressure: 0.28 Pa at 20°C and 0.47 Pa at 25°C, OECD TG 104 - thermogravimetric effusion method, 2020

Key value for chemical safety assessment

Vapour pressure:

0.47 Pa

at the temperature of:

25 °C

Additional information

Key study : EU Method A.4, 2020 : The vapour pressure was determined according to EU Method A.4 and OECD TG 104 using the thermogravimetric effusion method under GLP. The vapour pressure regression curve constructed using the data of Experiment 1 and Experiment 3 since coefficient of correlation was obtained at >0.99 only for this combination. The results from Experiment 2 were excluded from further analysis. The plot of the log PT of the test item as function of the reciprocal temperatures was performed. The equation of the curve was: log PT,20 = -4087 × 1/T + 13.38 (r = 0.995, n = 8). The vapour pressure of the test item was determined to be 0.28 Pa (or 2.1 x 10^-3 mm Hg) at 20°C, and 0.47 Pa (or 3.6 x 10^-3 mm Hg) at 25°C.