2-ethylhexanoic acid, cerium salt

Melting point / freezing point

Link to relevant study record(s)

Reference

Endpoint:

melting point/freezing point

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2018-01-03 to 2018-06-07

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Reason / purpose for cross-reference:

reference to same study

Qualifier:

according to guideline

Guideline:

OECD Guideline 102 (Melting point / Melting Range)

Version / remarks:

1995

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method A.1 (Melting / Freezing Temperature)

Version / remarks:

2008

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

2017-02-28

Type of method:

differential scanning calorimetry

Specific details on test material used for the study:

Storage conditions: Room temperature tightly closed

Atm. press.:

994 hPa

Decomposition:

yes

Decomp. temp.:

>= 135 °C

Sublimation:

no

Melting and Boiling Point (DSC)

In the temperature range of 50 °C – 200 °C, a broad endothermic effect was observed. Between 210 °C and 300 °C an exothermic effect was detected with a mean decomposition energy  of -90 J/g. A second broad endothermic effect was observed in the temperature range of 390 °C – 520 °C directly followed by an exothermic effect in the temperature range of 520 °C to 580 °C.

Results of the DSC-measurements

No.	Sample weight [mg]	Onset of Effect [°C]	Range of effect [°C]	Weight loss [mg]	Atmospheric pressure [hPa]
PN14350	22.36	85.49 --- 425.94 ---	50 – 200 (endo) 210 – 300 (exo) 390 – 520 (endo) 520 – 580 (exo)	16.80 75.13 %	994.1
PN14351	16.82	70.83 --- 439.01 ---	50 – 190 (endo) 210 – 290 (exo) 390 – 520 (endo) 520 – 570 (exo)	12.65 75.21 %	994.1

During the heating phase an untypical broad endothermic effect was observed in the temperature range of 50 °C – 200 °C, which cannot be assigned to a melting of the test item.

The test item showed a second broad endothermic signal in the temperature range of 390 °C – 520 °C, which cannot be assigned to a boiling of the test item. This endothermic effect may be caused by another endothermic process (e.g. gas evolution), as it is not observed in the thermal stability investigation, which is performed in a closed glass crucible. In view of the fact that the measured weight loss of each sample was only 75 % of the respective initial sample weight, none of the observed endothermic effects can be assigned to boiling of 2-ethylhexanoic acid, cerium salt.

Measurements by the capillary method

To verify the DSC measurements, the test item was additionally tested according to the capillary method. At a temperature of about 65 °C the test item (beige solid) sintered and the condition of the test item shows transparent. Above approx. 135 °C the top of the test item became yellow. At about 180 °C the colour of the test item was completely yellow-orange. At approx. 200 °C the colour changed again to white. After this the test item became darker until 300 °C. The measurement was stopped at 320 °C with a grey to brown residue remaining in the capillary.

In summary, the test item has no melting/boiling point up to the decomposition starting at a temperature of approx. 135 °C.

Thermal stability (DSC)

In the temperature range of 50 °C – 70 °C an endothermic effect was observed. In the temperature range of 190 °C – 250 °C an exothermic effect was observed with a mean decomposition energy of -120 J/g. A broad exothermic effect was observed in the temperature range of 470 °C – > 600 °C with an energy of <-700 J/g. In the DSC-measurement PN14356 the measurement was stopped at 585 °C by a DSC error.

Results of the DSC-measurements

No.	Sample weight [mg]	Start of effect [°C]	Energy* [J/g]
PN14355	7.75	50 (endothermic) 210 (exothermic) 470 (exothermic)	+10 -110 -700
PN14356	7.28	50 (endothermic) 190 (exothermic) 480 (exothermic)	+10 -140 -360

*Negative energy for exothermic processes, positive energy for endothermic processes

Conclusions:

Melting and Boiling Point:
The test item 2-ethylhexanoic acid, cerium salt has no melting and boiling point up to its decomposition starting at approx. 135 °C at atmospheric pressure (994 hPa) as determined by differential scanning calorimetry and as confirmed by the capillary method according to Regulation EC No. 440/2008 Method A.1./A.2. and OECD Test Guideline 102/103 (1995).

Thermal Stability:
The test item 2-ethylhexanoic acid, cerium salt showed an exothermic effect in the temperature range of 190 °C – 210 °C with a mean decomposition energy of -120 J/g and a second one in the temperature range of 470 °C – > 600 °C with a decomposition energy of <-700 J/g as determined according to OECD Test Guideline 113 (1981).

Description of key information

2-ethylhexanoic acid, cerium salt has no melting/boiling point up to the decomposition starting at approx. 135 °C at atmospheric pressure (994 hPa).

Additional information

Melting and Boiling Point:

The test item 2-ethylhexanoic acid, cerium salt has no melting and boiling point up to its decomposition starting at approx. 135 °C at atmospheric pressure (994 hPa) as determined by differential scanning calorimetry and as confirmed by the capillary method according to Regulation EC No. 440/2008 Method A.1. / A.2. and OECD Test Guideline 102 / 103 (1995).

Thermal Stability:

The test item 2-ethylhexanoic acid, cerium salt showed an exothermic effect in the temperature range of 190 °C – 210 °C with a mean decomposition energy of -120 J/g and a second one in the temperature range of 470 °C – > 600 °C with a decomposition energy of <-700 J/g as determined according to OECD Test Guideline 113 (1981).