Registration Dossier

Administrative data

Endpoint:
melting point/freezing point
Type of information:
experimental study
Adequacy of study:
key study
Study period:
from 12 June 2017 to 20 September 2017
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2017
Report Date:
2017

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
EU Method A.1 (Melting / Freezing Temperature)
Version / remarks:
2008
Deviations:
no
Qualifier:
according to
Guideline:
OECD Guideline 102 (Melting point / Melting Range)
Version / remarks:
1995
Deviations:
no
Qualifier:
according to
Guideline:
EPA OPPTS 830.7200 (Melting Point / Melting Range)
Version / remarks:
1998
Deviations:
no
GLP compliance:
yes
Type of method:
differential scanning calorimetry

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
solid
Remarks:
paste
Details on test material:
Name as cited in report: DDDA TEA salt
Physical appearance: beige to pale yellow paste
Storage conditions: at room temperature
Specific details on test material used for the study:
The test material is a paste at room temperature.

Results and discussion

Melting / freezing point
Key result
Melting / freezing pt.:
26.2 °C
Decomposition:
yes
Decomp. temp.:
> 50 °C
Remarks on result:
other: Glass transition point: -78.1°C.

Any other information on results incl. tables

DSC EXPERIMENT 1

During cooling no exothermic effects were observed. When starting to heat, a glass transition was showed. The inflection point could not be determined since it appeared too close to the minimum temperature of the experiment. From 50°C an endothermic effect was observed followed by an exothermic effect. The evaporation of water in the test sample might have caused the endothermic effect. This was most probably superimposed by reaction and/or decomposition of the test item causing the exothermic signal. After the experiment, a dark brown molten residue remained in the sample container. The change of the colour substantiated that the test item had reacted and/or decomposed. 

DSC EXPERIMENT 2

In order to investigate the glass transition, a lower cooling rate of 1°C/minute was applied. The inflection point of the glass transition was -78.896°C. An endothermic peak was observed between 0°C - 50°C with its max. at 26.696°C. The endothermic effect was most likely obtained due to melting of the test item. From 50°C an endothermic effect was observed followed by an exothermic effect. After the experiment, a dark brown molten residue remained in the sample container.

DSC EXPERIMENT 3

In order to investigate whether reaction and/or decomposition of the test item already occurred during melting, Experiment 3 was stopped directly after the melting peak.  Similar results as in Experiment 2 were obtained. The inflection point of the glass transition was -77.206°C. The peak max of the melting peak was 25.661°C. After the experiment, a pale yellow molten residue remained in the sample container. It demonstrated that melting was the reason for the endothermic effect and that reaction and/or decomposition of the test item did not occur at temperatures up to 50°C. 

DATA HANDLING

Melting point= mean peak max. of Experiment 2 (26.696°C) and Experiment 3 (25.661°C)

Glass transition point= mean inflection point of Experiment 2 (-78.896°C) and Experiment 3 (-77.206°C)

 

Applicant's summary and conclusion

Conclusions:
The melting point of the substance was determined to be 26.2°C.
The glass transition point of the substance was determined to be -78.1°C.


Executive summary:

Differential Scanning Calorimetry (DSC) experiments were performed in a GLP study according to EC A.1, OECD 102 and OPPTS 830.7200.

The melting temperature of the substance was determined in duplicate obtaining a mean value of 26.2°C.

The glass transition temperature of the substance was determined in duplicate obtaining a mean value of -78.1°C.

Reaction and/or decomposition of the substance occurs at temperatures above 50°C.