Hexane, 1,6-diisocyanato-, homopolymer, 2-hydroxyethyl acrylate- and propylene glycol monoacrylate-blocked

Vapour pressure

Link to relevant study record(s)

Reference

Endpoint:

vapour pressure

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

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:

not specified

Type of method:

effusion method: Knudsen cell

Key result

Temp.:

20 °C

Vapour pressure:

0 Pa

Key result

Temp.:

25 °C

Vapour pressure:

0 Pa

The following vapour pressures were determined experimentally and considered as valid (mean and standard deviation given):

Table 1: Experimentally Determined Vapour Pressures

T	T	P	Stand. Dev. P	RSD P
°C	K	Pa	Pa	%
90.0	363.2	6.89E-04	2.09E-04	30.4
105.0	378.2	1.66E-03	3.62E-04	21.8
120.0	393.2	3.46E-03	5.14E-04	14.8

For the test substance the following vapour pressures at 20 °C and at 25 °C were calculated from the regression equation:

- Vapour pressure at 20 °C: 4.44E-06 Pa

- Vapour pressure at 25 °C: 6.90E-06 Pa

The linear regression of log p vs. 1/T gave a correlation coefficient r of - 0.9996, showing good repeatability and precision. Therefore, the determination is considered as valid.

Conclusions:

Under the study conditions, vapour pressure of the substance was calculated to be 4.44E-06 at 20°C and 6.90E-06 at 25°C.

Executive summary:

A study was conducted to determine the vapour pressure of the substance according to OECD 104 and EU Method A.4. The test substance was weighed into the Knudsen cells. They were closed using a crimp-cap with hole and an aluminium plate with an aperture of 1 mm diameter. Four Knudsen cells were prepared in this way and set into the vacuum chamber. The vacuum chamber was evacuated to 10E-05 Pa or lower. Every day, vacuum was released; the Knudsen cells were taken out and weighed. After weighing, the cells were built in again and the vacuum was regenerated. Throughout the measurement, the temperature of the vacuum chamber was held constant using an electrical heating device (± 1.0°C). First, the determination was performed at 30°C. Then, further determinations were made at 45, 60, 75, 90, 105 and 120°C. Vapour pressures at 20°C and at 25°C were calculated from a regression equation. Under the study conditions, vapour pressure of the substance was established to be 4.44E-06 Pa at 20°C and 6.90E-06 Pa at 25°C (Krebs, 2016).

Description of key information

The vapour pressure was determined according to OECD Guideline 104 and EU Method A.4 (Krebs, 2016).

Key value for chemical safety assessment

Vapour pressure:

0 Pa

at the temperature of:

20 °C