Sodium 2-[[4-(cyclohexylamino)-9,10-dihydro-9,10-dioxo-1-anthryl]amino]-5-ethoxybenzenesulphonate

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:

From January 24th to February 07th, 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:

Adopted on 27 July 1995

GLP compliance:

yes (incl. QA statement)

Type of method:

differential scanning calorimetry

Remarks:

and capillary method

Decomposition:

yes

Decomp. temp.:

ca. 315 - 340 °C

DSC analysis

During the DSC heating up phase, an endothermic reaction was recorded between 62 and 102 °C, which can be reasonably attribute to the water release. Around the temperature of 315 °C the substance undergoes decomposition, throught a series of successive endo-exo-endo-thermic reactions.

At the start of the experiment, the substance appeared as a dark blue powder; at the end of the experiment the substance appeared as black powder. 

Replicate	Reaction	Onset (°C)	Endset (°C)	Peak (°C)	Energy (J/g)
Rep. 1	Endothermic	34.6	102.92	62.65	34.33
Rep. 2	Endothermic	50.58	116.04	64.82	30.95
Rep. 1	Endothermic	303.56	321.18	315.01	14.99
Rep. 2	Endothermic	303.12	321.18	315.37	15.27
Rep. 1	Exothermic	323.03	314.82	328.07	-15.21
Rep. 2	Exothermic	323.8	340.87	329.27	-14.35
Rep. 1	Endothermic	341.04	363.25	351.85	23.81
Rep. 2	Endothermic	341.14	363.04	351.72	21.76

Appearance of the test item

Replication no.	Appearance of test item	Initial weight of the test item, (mg)	Residue mg (%)	Appearance of test item at the end
R1	Dark blue granules	2.1	1.5 (71)	black powder
R2	Dark blue granules	2.1	1.4 (67)	black powder

Capillary test

Test item did not melt up to 250 °C and no visual change was observed.

Conclusions:

Decomposition before melting/boiling at ca 315 - 340 °C

Executive summary:

The thermal behaviour of the substance was investigated in accordance with the OECD guideline 102. For the differential scanning calorimetry experiment, the test item was weighed and placed into the crucible and the test was run with a closed crucible. The prepared capsule was inserted into the DSC apparatus and heated from room temperature up to 500 °C at a constant heating rate of 10 K/min. Before and after the test, the weight of the sample was determined. The measurements were performed under inert atmosphere. The experiment was performed in duplicate.

In order to confirm the DSC outcomes, an additional measurement with capillary method was performed in the temperature range of ca 25 – 250 °C. The experiment was carried out in duplicates.

During the DSC heating up phase, an endothermic reaction was recorded between 62 and 102 °C, which can be reasonably attribute to the water release. Around the temperature of 315 °C the substance undergoes decomposition, throught a series of successive endo-exo-endo-thermic reactions.

At the start of the experiment, the substance appeared as a dark blue powder; at the end of the experiment the substance appeared as black powder. 

Conclusion

The test item undergoes decomposition starting from approximately 315 °C up to 340 °C. No reactions of melting/boiling reaction attributable to the test item were recorded.

Description of key information

Decomposition before melting/boiling at ca. 315 - 340 °C

Additional information

OECD 102 - differential scanning calorimetry