N,N-bis(2-hydroxyethyl)glycine

Melting point / freezing point

Administrative data

Endpoint:

melting point/freezing point

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From 23 January 2017 to 16 March 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 guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

EU Method A.1 (Melting / Freezing Temperature)

Version / remarks:

2008

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

OECD Guideline 102 (Melting point / Melting Range)

Version / remarks:

1995

Deviations:

no

Test guideline 3

Qualifier:

according to guideline

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

Test material information

Constituent 1

Reference substance name:

N,N-bis(2-hydroxyethyl)glycine

EC Number:

205-755-1

EC Name:

N,N-bis(2-hydroxyethyl)glycine

Cas Number:

150-25-4

Molecular formula:

C6H13NO4

IUPAC Name:

N,N-bis(2-hydroxyethyl)glycine

impurity 1

Reference substance name:

N-(2-hydroxyethyl)ethylenediaminetriacetic acid

EC Number:

205-759-3

EC Name:

N-(2-hydroxyethyl)ethylenediaminetriacetic acid

Cas Number:

150-39-0

Molecular formula:

C10H18N2O7

IUPAC Name:

N-{2-[bis(carboxymethyl)amino]ethyl}-N-(2-hydroxyethyl)glycine

impurity 2

Reference substance name:

Not specified

IUPAC Name:

Not specified

impurity 3

Reference substance name:

Water

EC Number:

231-791-2

EC Name:

Water

Cas Number:

7732-18-5

Molecular formula:

H2O

IUPAC Name:

Dihydrogen oxide

Test material form:

solid: crystalline

Details on test material:

Appearance: white crystalline powder
Storage conditions: at room temperature protected from light

Results and discussion

Melting / freezing point

Key result

Melting / freezing pt.:

197.1 °C

Decomposition:

yes

Remarks on result:

other: Decomposition started during melting.

Any other information on results incl. tables

TGA EXPERIMENT (PRELIMINARY TEST)

From 190°C upwards the weight of the sample decreased significantly. At 197°C the sample weight had decreased by > 10%. At 293°C the sample weight had decreased by 25%.

DSC EXPERIMENT 1

-Endothermic peak between 175°C and 225°C (extrapolated onset temperature: 197.312°C). Based on the high purity of the substance and the observed weight loss in the TGA experiment, it was concluded that this effect was due to melting and reaction and/or decomposition.

-A second endothermic effect started from 250°C. This effect was due to decomposition and/or reaction of the substance.

-After the experiment, a dark orange molten residue remained in the sample container.

-DSC curve: see picture below.

DSC EXPERIMENT 2

- Extrapolated onset temperature of the endothermic melting/decomposition peak: 196.813°C.

- At the end of the experiment (at 225°C), there was a colourless molten residue in the sample container. From this it was concluded that melting and reaction/decomposition was the reason for this effect.

Applicant's summary and conclusion

Conclusions:

The melting temperature of the substance was determined to be 197°C. Reaction and/or decomposition started during melting.

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 197°C. Reaction and/or decomposition started during melting.