Reaction mass of 2-ethylhexyl (3-isocyanato-4-methylphenyl)carbamate and 2-ethylhexyl (5-isocyanato-2-methylphenyl)carbamate and 2-ethylhexyl (3-isocyanato-2-methylphenyl)carbamate

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:

15. May 2018 to 17. May 2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 102 (Melting point / Melting Range)

Version / remarks:

OECD Guideline for the Testing of Chemicals No. 102 dated 27. July 1995 “Melting Point / Melting Range"

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method A.1 (Melting / Freezing Temperature)

Version / remarks:

Regulation (EC) No 440/2008 of 30 May 2008, published on 31. May 2008, Method A.1, “Melting/Freezing Temperature”

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

differential scanning calorimetry

Specific details on test material used for the study:

No further details specified in the study report.

Key result

Melting / freezing pt.:

>= -57.61 - < -40.53 °C

Decomposition:

no

Sublimation:

no

Remarks on result:

other: Atm. press. not specified

Pre-Test

Values Pre-Test

Room temperature	4.8 °C	-19.5 °C	-80 °C
Clear slightly green-ish, viscous liquid	Same as room temperature	More viscous than at room temperature, nor flowable anymore	Solid like ice

 

Calibration

Values DSC Indium

Expected Melting point	Measured Melting point	Expected Energy	Measured Energy	Assessment
156.6 ± 1.0 °C	156.55 °C (onset)	28.45 ± 1.0 J/g	28.60 J/g	OK

The measurement of indium after calibration met the validity criteria.

 

DSC Measurement of the Test Item

First determination

Values DSC Test Item first determination

	Temperature [°C]	Energy
Freezing Point	-55.07 (Onset) Range (Event marker) -54.76 to -62.61	-0.18 [J/g] (the minus symbol is stated for the energy of exothermic event)
Melting Point	-53.11 (Onset) Range (Event marker) -57.20 to -40.69	1.90 [J/g]

 

Repetition second determination

Values DSC Test Item second determination

	Temperature [°C]	Energy
Freezing Point	-55.57 (Onset) Range (Event marker) -55.29 to -63.27	-0.73 [J/g] (the minus symbol is stated for the energy of exothermic event)
Melting Point	-51.90 (Onset) Range (Event marker) -54.18 to -40.53	1.63 [J/g]

 

The deviation between the first and second determination was too high (> 0.5 K) and the peaks of two determinations were different; therefore, a third measurement was performed with a new crucible.

 

Third determination

Values DSC Test Item third determination

	Temperature [°C]	Energy
Freezing Point	No event visible	No event visible
Melting Point	-53.55 (Onset) Range (Event marker) -57.61 to -42.55	1.72 [J/g]   4.70 mW – 5.44 mW

 

Observations

Values Observations

	Mass test item	Mass crucible (before measurement):	Mass crucible (after measurement):	Observations
First Measurement	4.93 mg	50.10 mg	50.10 mg	The crucible was optically unchanged after measurement
Repetition Second Measurement	4.93 mg	50.10 mg	50.10 mg	The crucible was optically unchanged after measurement
Third Measurement	5.10 mg	50.44 mg	50.44 mg	The crucible was optically unchanged after measurement

 

Interpretation

In the first and second DSC measurements a flat and broad exothermic event during the cooling down phase was detected.

The exothermic event can be identified as freezing range (-54.76°C - -63.27°C) (evaluated with the event marker function).

In the heating up phase, a flat and broad endothermic event was detected in every measurement. This endothermic Event can be identified as melting range (-57.61°C - -40.53°C) (evaluated with the event marker function).

Conclusions:

The determination of the melting point of Trixene AS was performed via DSC (differential scanning calorimetry)
In the first and second DSC measurements a flat and broad exothermic event during the cooling down phase was detected. In the third no event could be clearly detected.
The exothermic event can be identified as freezing range (-54.76°C - -63.27°C) (evaluated with the event marker function).
In the heating up phase, a flat and broad endothermic event was detected in every measurement. This endothermic Event can be identified as melting range (-57.61°C - -40.53°C) (evaluated with the event marker function).
No observations were made which might cause doubts on the validity of the study outcome. Therefore, the result of the study is considered valid.

Executive summary:

Determination of the melting point of Trixene AS according to OECD 102 resp. EU A.1

 

Findings and Results:

The melting point was determined via DSC (differential scanning calorimetry)

Referring to the pre-test the melting point should be between -20 °C and -80 °C.

In the first and second DSC measurements a flat and broad exothermic event during the cooling down phase was detected. In the third no event could be clearly detected.

The exothermic event can be identified as freezing range (-54.76°C - -63.27°C) (evaluated with the event marker function).

In the heating up phase, a flat and broad endothermic event was detected in every measurement. This endothermic event can be identified as melting range (-57.61°C - -40.53°C) (evaluated with the event marker function).

No observations were made which might cause doubts on the validity of the study outcome. Therefore, the result of the study is considered valid.

Description of key information

melting range (-57.61°C - -40.53°C)

Key value for chemical safety assessment

Melting / freezing point at 101 325 Pa:

-40.53 °C

Additional information

The melting point was determined via DSC (differential scanning calorimetry)

Referring to the pre-test the melting point should be between -20 °C and -80 °C.

In the first and second DSC measurements a flat and broad exothermic event during the cooling down phase was detected. In the third no event could be clearly detected.

The exothermic event can be identified as freezing range (-54.76°C - -63.27°C) (evaluated with the event marker function).

In the heating up phase, a flat and broad endothermic event was detected in every measurement. This endothermic event can be identified as melting range (-57.61°C - -40.53°C) (evaluated with the event marker function).

No observations were made which might cause doubts on the validity of the study outcome. Therefore, the result of the study is considered valid.