2-hydroxy-1-[4-[4-(2-hydroxy-2-methylpropanoyl)phenoxy]phenyl]-2-methylpropan-1-one

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:

2018-11-29 - 2018-12-03 (experimental phase)

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Reason / purpose for cross-reference:

reference to same 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

Melting / freezing pt.:

99.96 - 101.44 °C

Atm. press.:

990 - 1 003.5 hPa

Decomposition:

yes

Decomp. temp.:

285

During the heating phase a distinct endothermic effect was observed in the temperature range of 100 – 110 °C, which can be assigned to the melting of the test item. As the onset temperatures in both tests do deviate by less than 0.5 K from their mean value of 100.7 °C, a melting range of 100.0 - 101.4°C is given instead of a melting point.

A second endothermic effect was detected in the temperature range of 340 – 430 °C, which could not be clearly assigned to the boiling of the test item. Thus, the capillary method was performed.

Table: Results of the DSC-measurements

Sample weight / mg	Onset of effect / °C	Range of effect / °C	Weight loss / mg	Atmospheric pressure / hPa
12.66	101.44 -	100 – 110 (endo) 350 – 430(endo)	10.01	990.0
12.97	99.96 -	100 – 110 (endo) 340 – 430 (endo)	10.24	1003.5

Capillary Method

For verification of the result for the melting temperaturethe test item was additionally tested three times according to the capillary method. In the three tests, the test item melted at an average temperature of 100.8 °C.

The molten test item was subject to a second test series according to the capillary method. Upon heating of the test item it changed its colour from transparent to yellow at approx. 285 °C and gas evolution was visible. At a temperature of approx. 310 °C the test item turned orange-brownish and evolution of gas continued. At a temperature of approx. 375 °C the test item turned dark brown and evolution of gas continued. At a temperature of 400 °C the test item turned black and foamed. At a temperature of 400 °C the test was ended.

The measurement carried out according to the capillary method showed that the second endothermic effect observed in the DSC measurements can be assigned to decomposition of the test item with concomitant gas evolution. Due to this result, no boiling point can be assigned to the test item.

Conclusions:

- melting range (at 990.0 - 1003.5 hPa): 100.0 - 101.4 °C
- melting point (at 990.0 - 1003.5 hPa): 100.7 °C (mean value)

Executive summary:

The test item 2-Hydroxy-1-[4-(4-(2-hydroxy-2-methylpropionyl)phenoxy)phenyl]-2-methylpropan-1-one has a melting range of 100.0 – 101.4 °C as determined by differential scanning calorimetry and capillary method [according to EU Method A.1. and OECD Test Guideline 102].

Description of key information

The melting point of the test substance was determined by differential scanning calorimetry according to OECD Guideline 102 and EU Method A.1 (Schiewer, 2019).

Key value for chemical safety assessment

Melting / freezing point at 101 325 Pa:

100.7 °C