Cyclopropanecarboxylic acid, 2-[1-(3,3-dimethylcyclohexyl)ethoxy]-2-methylpropyl ester

Vapour pressure

Link to relevant study record(s)

Reference

Endpoint:

vapour pressure

Type of information:

experimental study

Adequacy of study:

key study

Study period:

12-05-2004 to 14-05-2004

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: 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

GLP compliance:

yes

Type of method:

dynamic method

Temp.:

20 °C

Vapour pressure:

1.5 Pa

Remarks on result:

other: ± 0.1 Pa

Table 1.0 – Vapour Pressure of test item at 3 different temperatures

Measurement	Temperature		Mean Vapour Pressure
	°C	K	p	±	ln P	±
3 -16	37.61	310.76	5.91	0.04	1.78	0.01
19 – 31	32.24	305.39	3.84	0.02	1.35	0.01
32 - 43	25.10	298.25	2.25	0.04	0.81	0.02

 

Discussion

Fitting these data using the least squares method gives a value of 1.47 Pa for the vapour pressure of the test substance at 20°C. The error for the vapour pressure (p) calculated from the fit was 4.4 %. The deviation between each of the three data points and the fit was < or = 1.8 %. The error made in estimating the mean vapour pressure per temperature series was < or = 0.8 %. Taking all these errors into account, a value of 0.1 Pa (i.e. 6.8 %) was found to be reasonable for the uncertainty in the calculated vapour pressure at 20°C.

Note: Under OECD TG 109, The static method recommended range is 10 to 10^5 Pa. However, when using a capacitance manometer, the Static method can be used below 10^-1 Pa. Details are provided in the full study report.

Conclusions:

The vapour pressure of the substance has been determined to be 1.5 ± 0.1 Pa at 20°C.

Executive summary:

The vapour pressure was determined using EU Method A.4 and OECD TG 109 using the static method under GLP, with the use of a capacitance manometer. The Static Method can be used to determine the vapour pressure at 20°C. In the static process, at thermodynamic equilibrium, the vapour pressures established in a closed system are determined at three specific temperatures. The static method recommended range is 10 to 10^5 Pa. However, when using a capacitance manometer, the Static method can be used below 10^-1 Pa. The measured results (In p) are plotted versus the reciprocal temperature (in Kelvin) and yield a rectilinear curve for the limited temperature range. The vapour pressure at 20°C was calculated from this curve. A total of 43 measurements were performed. Fitting the data using the least squares method gives a value of 1.47 Pa for the vapour pressure of the test substance at 20°C. The error for the vapour pressure (p) calculated from the fit was 4.4 %. The deviation between each of the three data points and the fit was < or = 1.8 %. The error made in estimating the mean vapour pressure per temperature series was < or = 0.8 %. Taking all these errors into account, a value of 0.1 Pa (i.e. 6.8 %) was found to be reasonable for the uncertainty in the calculated vapour pressure at 20°C. The vapour pressure of the substance has been determined to be 1.5 ± 0.1 Pa or 1.1 ± 0.1 x10^-2 mm Hg at 20°C..

Description of key information

Vapour Pressure: 1.5 ± 0.1 Pa or 1.1 ± 0.1 x10^-2 mm Hg at 20°C, EU Method A.4 – Static Method with capacitance manometer, 2004

Key value for chemical safety assessment

Vapour pressure:

1.5 Pa

at the temperature of:

20 °C

Additional information

Key study : EU Method A.4, 2004 : The vapour pressure was determined using EU Method A.4 and OECD TG 109 using the static method under GLP, with the use of a capacitance manometer. The Static Method can be used to determine the vapour pressure at 20°C. In the static process, at thermodynamic equilibrium, the vapour pressures established in a closed system are determined at three specific temperatures. The static method recommended range is 10 to 10^5 Pa. However, when using a capacitance manometer, the Static method can be used below 10^-1 Pa. The measured results (In p) are plotted versus the reciprocal temperature (in Kelvin) and yield a rectilinear curve for the limited temperature range. The vapour pressure at 20°C was calculated from this curve. A total of 43 measurements were performed. Fitting the data using the least squares method gives a value of 1.47 Pa for the vapour pressure of the test substance at 20°C. The error for the vapour pressure (p) calculated from the fit was 4.4 %. The deviation between each of the three data points and the fit was < or = 1.8 %. The error made in estimating the mean vapour pressure per temperature series was < or = 0.8 %. Taking all these errors into account, a value of 0.1 Pa (i.e. 6.8 %) was found to be reasonable for the uncertainty in the calculated vapour pressure at 20°C. The vapour pressure of the substance has been determined to be 1.5 ± 0.1 Pa or 1.1 ± 0.1 x10^-2 mm Hg at 20°C.