4-(1,1-dimethylethyl)cyclohexyl methacrylate

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 starting date: 03 January 2017 Experimental completion date: 23 March 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

Specific details on test material used for the study:

Identification: 4-tert-butylcyclohexyl methacrylate
(CAS 46729-07-1)
Appearance/physical state: clear colourless liquid (on melting)
Batch: DAR-16030
Purity: 89.2%
Expiry / retest date: 01 August 2018
Storage conditions: approximately 4 °C, in the dark

Key result

Melting / freezing pt.:

ca. -4 - ca. 42 °C

Evaluations starting at 0 °C

Thermographic Data for determination 1 and 2

Determination	Thermal Event	Interpretation	Temperature
			ºC	K
1	Endotherm range	Apparent melting temperature range	22.72 to 42.01	296 to 315
2	Endotherm range	Apparent melting temperature range	26.57 to 41.20	300 to 314

 

Overall result:            An apparent melting temperature range of approximately 23 to 42 °C (296 to 315 K)

Evalutaions starting at -25 °C

Thermographic Data for determination 3,4 and 5

Determination	Thermal Event	Interpretation	Temperature
			ºC	K
3	Endotherm range	Melting temperature range	-4.05 to 29.38	269 to 303
4	Endotherm range	Melting temperature range	up to 36.34	up to 309
5	Endotherm range	Melting temperature range	-0.87 to 40.55	272 to 314

 

Overall result from all determinations: A melting temperature range of approximately -4 to 42 °C (269 to 315 K)

Discussion

On use of the test item at its storage temperature of approximately 4 °C, it was commonly observed as a wet looking crystalline solid. When using a starting temperature of 0 °C for the DSC evaluations, a broad melting endotherm was observed as expected. However a further replicate sample analyzed under these conditions resulted in no visible endotherm, indicating that perhaps analyzed samples contained a proportion of liquid phase (as small sample quantities can readily supercool in the crucibles). Testing was therefore adapted to employ a lower initial starting temperature.

Testing with an initial starting temperature of -25 °C was performed in a nitrogen atmosphere to avoid freezing of ambient air moisture in the sample furnace during the determinations.

On starting each determination at -25 °C, a much lower endotherm start temperature was observed, supporting the previous suspicion. It was not possible to quantify the endotherm onset temperature for determination 4, as it was truncated by an exothermic event. This exotherm can be attributed to the solidification of the test item during the run, further indicating the willingness of the test item to supercool.

As a result of the initial low rate of enthalpy change during the start of the melting process, the onset temperatures could only be approximated. The variability in the melting ranges quantified was acknowledged but considered characteristic of the test item. To incorporate this behaviour into regulatory data, the overall observed melting temperature range of approximately -4 to 42 °C (269 to 315 K) has been reported as the conclusion of the evaluations performed.

Conclusions:

The melting temperature range of the test item has been determined to be approximately -4 to 42 °C (269 to 315 K).

Executive summary:

The melting temperature range of the test item has been determined to be approximately-4 to 42 °C (269 to 315 K).Testing was performed by differential scanning calorimetry,using a procedure designed to be compatible with Method A.1 Melting/Freezing Temperature of Commission Regulation (EC) No 440/2008 of 30 May 2008 and Method 102 of the OECD Guidelines for Testing of Chemicals, 27 July 1995.

Description of key information

The melting point was determined to be -4 to 42 oC. The product as tested is visually a liquid, therefore, for the chemical safety assessment, a value < 20 oC should be used and -4 oC is chosen.

Key value for chemical safety assessment

Melting / freezing point at 101 325 Pa:

-4 °C