2-Propenoic acid, homopolymer

Vapour pressure

Link to relevant study record(s)

Reference

Endpoint:

vapour pressure

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From 2016-10-06 to 2016-12-14

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 104 (Vapour Pressure Curve)

Deviations:

yes

Remarks:

Due to the test item nature, methodology was adapted in regards to initial study plan.

Qualifier:

according to guideline

Guideline:

EU Method A.4 (Vapour Pressure)

Deviations:

yes

Remarks:

Due to the test item nature, methodology was adapted in regards to initial study plan.

GLP compliance:

no

Type of method:

static method

Specific details on test material used for the study:

- Analytical purity: >=99%
- Purity test date: 24 August 2016
- Lot/batch No.: BA5H22021
- Expiration date of the lot/batch: 24 August 2017
- Appearance: Colourless limpid liquid
- Storage: In darkness at room temperature

Key result

Temp.:

20 °C

Vapour pressure:

264 Pa

Key result

Temp.:

25 °C

Vapour pressure:

357 Pa

Table 1: Data recorded during the experiment

Texp (°C)	Pexp (mbar)	1/Texp (K^-1)	Ln (Pexp) with Pexpin mbar
21.52	2.91	0.00339	1.07
21.51	2.91	0.00339	1.07
21.52	2.91	0.00339	1.07
40.63	8.49	0.00319	2.14
40.63	8.49	0.00319	2.14
40.63	8.49	0.00319	2.14
50.30	13.73	0.00309	2.62
50.30	13.75	0.00309	2.62
50.31	13.74	0.00309	2.62
31.11	5.03	0.00329	1.62
31.10	5.03	0.00329	1.62
31.11	5.03	0.00329	1.62

After measuring the first four temperatures, the test item began to polymerize. The measurements were stopped to preserve the measurement cell. This justifies the deviation from the study plan.

The uncertainty of measurement for pressure was about +/- 0.03 mbar and for temperature, it was about +/- 0.05°C. These are the maximum deviations measured during the pressure and temperature calibrations.

The measured vapour pressures were used to regress the coefficients of Antoine's law reported in Table 2 using the following equation. They enable to calculate the vapour pressure of the test item at any given temperature provided this temperature falls within the range specified in the same table.

Ln P_cal= A + (B/T+C)

With Pcal (calculated pressure) in mbar and T in K

Table 2: Antoine's law coefficients

A	B	C	Texpmin (°C)	Texpmax (°C)
15.37692	-3374.17435	-58.94220	21.52	50.30

The maximum error involved by the modelling of vapour pressure with our Antoine’s law is about 0.03 mbar which is in magnitude of the uncertainty of measurement of pressure.

Table 3: Average of measured values and calculated data with Antoine’s law coefficients

Texp (°C)	Pexp (mbar)	Pcalc (mbar)	Pexp-Pcalc (mbar)
21.52	2.91	2.89	0.02
31.11	5.03	5.07	-0.04
40.63	8.49	8.47	0.02
50.30	13.74	13.74	0.00

Conclusions:

The vapour pressure of the test item was calculated to be 264 Pa +/- 3 Pa at 20°C, and 357 Pa +/- 3 Pa at 25°C, using the Antoine's law.

Executive summary:

The vapour pressure of the REACH substance was determined in a non-GLP study performed in accordance with EU A.4 method and OECD Guideline No. 104, using the static method. The vapour pressure of the test item was calculated to be 264 Pa +/- 3 Pa at 20°C, and 357 Pa +/- 3 Pa at 25°C, using the Antoine's law.

Description of key information

The vapour pressure of the REACH substance was determined in a non-GLP study performed in accordance with EU A.4 method and OECD Guideline No. 104, using the static method. The vapour pressure of the test item was calculated to be 264 Pa +/- 3 Pa at 20°C, and 357 Pa +/- 3 Pa at 25°C, using the Antoine's law.

Key value for chemical safety assessment

Vapour pressure:

357 Pa

at the temperature of:

25 °C

Additional information

The vapour pressure of the REACH substance was determined in one non-GLP study performed in accordance with standard methods, without deviations. The study is considered as reliable (Klimisch 1) and was selected as a key study for the endpoint.