A mixture of cis- and trans-cyclohexadec-8-en-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:

from 2021-05-26 to 2021-06-02

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:

1995

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method A.1 (Melting / Freezing Temperature)

Version / remarks:

2008

Deviations:

no

GLP compliance:

no

Type of method:

differential scanning calorimetry

Key result

Melting / freezing pt.:

25 °C

Atm. press.:

1 001.3 hPa

Decomposition:

no

Sublimation:

no

DSC-measurements

During cooling a first exothermic effect was observed at approx. 20 °C and a second between -50 – -70 °C. During heating a first endothermic effect was observed in the temperature range of -70 – -30 °C. A second endothermic effect was detected in the temperature range of 20 – 40 °C. Between 220 – 360 °C a third endothermic effect could be detected.

 

Results of the DSC-measurements during cooling

Sample weight / mg	Onset of Effect / °C	Range of effect / °C	Weight loss / mg	Atmospheric pressure / hPa
10.70	17.89 -60.69	Approx.. 20 (exo) -50 - -70 (exo)	10.71	1001.3
9.52	15.55 -57.63	Approx.. 20 (exo) -50 - -70 (exo)	9.54	1001.3

 

Results of the DSC-measurements during heating

Sample weight / mg	Onset of Effect / °C	Range of effect / °C	Weight loss / mg	Atmospheric pressure / hPa
10.70	-63.07 24.57 333.07	-70 - -30 (endo) 20 - 40 (endo) 220 - 360 (endo)	10.71	1001.3
9.52	-62.21 25.39 336.04	-70 - -30 (endo) 20 - 40 (endo) 220 - 360 (endo)	9.54	1001.3

 

During the heating phase two endothermic effects with corresponding exothermic effects during the cooling phase were observed up to 40 °C, at which the substance is liquid. By visual inspection of the substance cooled to 0.8 °C in a test tube the thermic effect at approx. 20 °C could be identified as freezing and melting effect, respectively. The second effect at approx. -60 °C might be explained by different melting points of cis- and trans-isomers, but was not further investigated in this study.

As the onset temperatures in both tests during the warming up do not deviate by more than 0.5 K from their mean value of 24.98 °C, this temperature can be used as melting point. The test item has a melting point of 25.0 °C, which could be confirmed by the visual inspection in a cooled test tube (25 °C).

Conclusions:

The melting point of the test item was determined to be 25.0 °C.

Executive summary:

An experimental study was conducted according to Regulation (EC) No 440/2008 Methods A.1. and OECD Test Guidelines 102 to determine the melting point of the test item. The test item was mostly solid, partly molten when it was delivered. In order to take a representative sample, the substance was completely molten at 40 °C and the substance remained liquid at ambient temperature. Therefore, the tests were started with the liquid state of the substance. The crucibles were firstly cooled down at a constant cooling rate of -0.25 K/min to -90 °C. Afterwards, the temperature was increased up to 500 °C at a constant heating rate of 10 K/min under air. During cooling a first exothermic effect was observed at approx. 20 °C and a second between -50 – -70 °C. During heating a first endothermic effect was observed in the temperature range of -70 – -30 °C. A second endothermic effect was detected in the temperature range of 20 – 40 °C. During the heating phase two endothermic effects with corresponding exothermic effects during the cooling phase were observed up to 40 °C, at which the substance is liquid. By visual inspection of the substance cooled to 0.8 °C in a test tube the thermic effect at approx. 20 °C could be identified as freezing and melting effect, respectively. The second effect at approx. -60 °C might be explained by different melting points of cis- and trans-isomers, but was not further investigated in this study. As the onset temperatures in both tests during the warming up do not deviate by more than 0.5 K from their mean value of 24.98 °C, this temperature can be used as melting point. The test item has a melting point of 25.0 °C, which could be confirmed by the visual inspection in a cooled test tube (25 °C).

Description of key information

The melting point of the test item was determined to be 25.0 °C.

Key value for chemical safety assessment

Melting / freezing point at 101 325 Pa:

25 °C

Additional information

An experimental study was conducted according to Regulation (EC) No 440/2008 Methods A.1. and OECD Test Guidelines 102 to determine the melting point of the test item. The test item was mostly solid, partly molten when it was delivered. In order to take a representative sample, the substance was completely molten at 40 °C and the substance remained liquid at ambient temperature. Therefore, the tests were started with the liquid state of the substance. The crucibles were firstly cooled down at a constant cooling rate of -0.25 K/min to -90 °C. Afterwards, the temperature was increased up to 500 °C at a constant heating rate of 10 K/min under air. During cooling a first exothermic effect was observed at approx. 20 °C and a second between -50 – -70 °C. During heating a first endothermic effect was observed in the temperature range of -70 – -30 °C. A second endothermic effect was detected in the temperature range of 20 – 40 °C. During the heating phase two endothermic effects with corresponding exothermic effects during the cooling phase were observed up to 40 °C, at which the substance is liquid. By visual inspection of the substance cooled to 0.8 °C in a test tube the thermic effect at approx. 20 °C could be identified as freezing and melting effect, respectively. The second effect at approx. -60 °C might be explained by different melting points of cis- and trans-isomers, but was not further investigated in this study. As the onset temperatures in both tests during the warming up do not deviate by more than 0.5 K from their mean value of 24.98 °C, this temperature can be used as melting point. The test item has a melting point of 25.0 °C, which could be confirmed by the visual inspection in a cooled test tube (25 °C).