3-ETHYL-5,5-DIMETHYL-GAMMA BUTYROLACTONE

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:

Experimental Dates: 02 to 04 December 2020

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

The study was conducted according to an internationally recognised method, with no deviation, and under GLP. The test substance is adequately characterised. Therefore full validation applies.

Qualifier:

according to guideline

Guideline:

OECD Guideline 102 (Melting point / Melting Range)

Version / remarks:

27 July 1995

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method A.1 (Melting / Freezing Temperature)

Version / remarks:

Commission Regulation (EC) No 440/2008

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

signed on 15 Nov. 2018

Type of method:

differential scanning calorimetry

Key result

Melting / freezing pt.:

18.3 °C

First Determination

Mass taken: 14.15 mg
Freezing peak was observed during the cooling phase at -10.4°C.
During the heating phase, the melting point of the substance was observed at 18.3°C.

Second Determination

Mass taken: 14.35 mg
Freezing peak was observed during the cooling phase but no endset value can be calculated as the DSC curve performs a loop at the summit of the peak. This loop corresponds with the increase of the temperature during the freezing of the test item (exothermic reaction).
During the heating phase, the melting point of the substance was observed at 20.3°C.

As the melting point values of determinations 1 and 2 did not respect validity criteria (no more than 0.5°C of difference up to 326.85°C), a third determination was performed.

Third Determination

Mass taken: 13.54 mg
Freezing peak was observed during the cooling phase at -11.8°C.
During the heating phase, the melting point of the substance was observed at 18.2°C.

Executive summary:

The melting point of the test substance was determined under GLP according to OECD 102 / EU A1 guideline, using the DSC method.

Three main runs were performed. A single peak, correponding to melting, was recorded in each determination, and the average of two onset determinations within accuracy criteria was retained.

The melting temperature of the test substance was determined to be 18.3°C.

Moreover the freezing point was observed as a single peak at -10.4°C (determination 1) and -11.8°C (determination 3).

Description of key information

Experimental melting point (i.e. transition from solid to liquid) = 18.3°C (OECD 102, DSC; GLP)

Freezing point (i.e. transition from liquid to solid) ca -11°C, suggesting supercooling.

Key value for chemical safety assessment

Melting / freezing point at 101 325 Pa:

18.3 °C

Additional information

A fully reliable experimental study, conducted according to a recognized OECD/EC method and under GLP, is available. It is considered as key study, and the result is retained as key data.