Disodium piperazine-1,4-diethanesulphonate

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:

05 October 2017 to 08 November 2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 102 (Melting point / Melting Range)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method A.1 (Melting / Freezing Temperature)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

differential scanning calorimetry

Key result

Decomposition:

yes

Remarks:

melting not occur before decomposition

Decomp. temp.:

> 375 °C

Remarks on result:

not determinable

Remarks:

melting of the test item was not observed below the temperature at which item decomposes

Preliminary test

The TGA curve of the test item is shown in Figure 1. Starting at 425°C, the weight of the sample decreased significantly. At 450°C, the sample weight had decreased by 25%. After the experiment, a black residue remained in the sample container (original colour: white). The change of the colour indicated reaction and/or decomposition of the test item.

Main study

The DSC curve obtained with Experiment 1 is shown in Figure 2. An endothermic peak was observed between 25°C and 100°C. Based on small weight loss observed between 50°C and 100°C during the preliminary test, the endothermic effect was most probably due to evaporation of volatile components. Another endothermic peak was observed between 375°C and 400°C. After the experiment, a grey residue remained in the sample container (original colour: white). Therefore, the endothermic effect was considered due to reaction and/or decomposition of the test item.

Conclusions:

The melting temperature of 1,4 piperazinediethanesulfonic acid disodium salt was tested by DSC.
Reaction and/or decomposition of the test item was observed during DSC experiments at temperatures of > 375°C (> 648K). Melting of the test item was not observed below the temperature at which reaction and/or decomposition started. Based on this, the test item has no melting temperature.

Description of key information

Reaction and/or decomposition of the test item was observed during DSC experiments at temperatures of > 375°C (> 648K).  Melting of the test item was not observed below the temperature at which reaction and/or decomposition started.  Based on this, the test item has no melting temperature.