Acetic acid, 2,2-difluoro-2-[[2,2,4,5-tetrafluoro-5-(trifluoromethoxy)-1,3-dioxolan-4-yl]oxy]-, ammonium salt (1:1)

Boiling point

Link to relevant study record(s)

Reference

Endpoint:

boiling point

Type of information:

experimental study

Adequacy of study:

key study

Study period:

20 December 2010 to 20 January 2011

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

Guideline-conform study under GLP.

Qualifier:

according to guideline

Guideline:

OECD Guideline 103 (Boiling point/boiling range)

Deviations:

yes

Remarks:

Deviations are considered to have no impact on quality and integrity of the study

Qualifier:

according to guideline

Guideline:

EU Method A.2 (Boiling Temperature)

Deviations:

yes

Remarks:

Deviations are considered to have no impact on quality and integrity of the study

GLP compliance:

yes (incl. QA statement)

Type of method:

method according to Siwoloboff

Key result

Atm. press.:

ca. 1 005 hPa

Decomposition:

yes

Decomp. temp.:

ca. 138 °C

Remarks on result:

not determinable

Remarks:

The boiling point of test item c-C6O4-COONH4 could not be determined since the test item decomposes before boiling.

Preliminary Test

In the preliminary test formation of gas at the boiling capillary was observed at 147.5 °C.

Decomposition Temperature

The test item melted to a turbid, milky-white liquid, which became colourless with uprising temperature. Small bubbles were observed beside the bigger bubbles rising from the boiling capillary, which could indicate decomposition or boiling. The results of two independent measurements of this point within±2 K are given in the following table:

Measured Decomposition Temperatures

(Atmospheric pressure of 1005 hPa)

Replicate No.	2	3
Point of first bubbles rising^1)[°C]	137.6	137.1
Decomposition Temperature^2)[°C]	138.5	138.4
Mean Value [°C]	138
Mean Value [K]	411

1)    Indicated visually

2)    Automatically detected by the apparatus

To decide whether boiling or decomposition was observed, the test item was heated to 140 °C in duplicates and observed over a period of 35 min at constant temperature. Immediately formation of small bubbles in the clear, colourless liquid was observed. After approx. 6 min a white residue was observed at the meniscus of the liquid test item. The observed formation of gas bubbles was not constant; it changed from intense to very slight gas formation. Due to these observations the determined temperature was defined as beginning of decomposition.

For further clarification one sample of the test item was heated from 130 °C to 250 °C with a heating rate of 10 °C/min. The results and observations are given in the following table:

Observations of the test item decomposition

Approx. Temperature [°C]	Observation
> 150	Gas formation becomes more intense
> 170	Continuous chain of bubbles
> 190	Slight colour change of the liquid to brown
> 200	Very intense gas formation
> 210	Fume formation at top ofboiling point tube
> 220	End of decomposition forming a white‑brownish solid residue

Conclusions:

The boiling point of test item cC6O4 ammonium salt could not be determined since the test item decomposes before boiling.
The beginning of the decomposition of the test item cC6O4 ammonium salt was determined to be at 411 K (138 °C) under an atmospheric pressure of 1005 hPa.

Executive summary:

The boiling point of cC6O4 ammonium salt (batch number:156/17) was determined according toOECD-Guideline No. 103 for Testing of Chemicals and to Council Regulation (EC) No. 440/2008 Method A.2 from 2010-12-21 to 2010-12-22 at Dr.U.Noack-Laboratorien, 31157 Sarstedt, Germany.

 

The approach for the determination of the boiling point of cC6O4 ammonium salt was performed with a capillary tube in a metal block apparatus at an atmospheric pressure of 1005 hPa.

During the testing a gas formation was observed at 138 °C. With respect to the test item structure a boiling at this low temperature was not expected. This consideration was verified by further heating of the test item above 138 °C. At 140 °C (constant for 35 min) the gas production decreased significantly, confirming the beginning of the thermal decomposition at 139 °C. At a temperature of approx. 200 °C intense decomposition with excessive release of gaseous decomposition products, resulting in a white to brown solid residue was observed.

Description of key information

The determination of the boiling point of the test item was performed according to the OECD Guideline 103 (Boiling point/boiling range) and the EU Method A.2 (Boiling Temperature).

The boiling point of test item cC6O4 ammonium salt could not be determined since the test item decomposes before boiling.

The beginning of the decomposition of the test item cC6O4 ammonium salt was determined to be at 411 K (138 °C) under an atmospheric pressure of 1005 hPa.

Key value for chemical safety assessment

Temperature of decomposition (state purity):

138 °C

Additional information

The boiling point of test item cC6O4 ammonium salt could not be determined since the test item decomposes before boiling.

The beginning of the decomposition of the test item cC6O4 ammonium salt was determined to be at 411 K (138 °C) under an atmospheric pressure of 1005 hPa.