Trichloro(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)silane

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:

2015-12-03 to 2016-02-08

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:

no

Other quality assurance:

ISO/IEC 17025 (General requirements for the competence of testing and calibration laboratories)

Type of method:

differential scanning calorimetry

Key result

Melting / freezing pt.:

-21 °C

Atm. press.:

1 013 hPa

Decomposition:

no

Preliminary thermogravimetric measurement

A preliminary thermogravimetric measurement was performed over a temperature range from room temperature to ca. 600°C.

Beginning at room temperature the mass loss rate increased steadily, reaching a maximum at 150°C. At approximately 160°C the mass loss was practically complete, considering the initial mass loss from purging (ca. 0.5 %) before the start of the measurement. Until 600 °C there was no residue left (TGA curve attached).

DSC measurements

The DSC measurements were performed twice.

After cooling to -150°C at a rate of 2 K/min the sample was heated to 300°C at a rate of 5 K/min. The cooling curve exhibits a broad, not very sharp exothermic crystallisation peak with multiple maxima at around -45°C.

It is to be noted that crystallisation processes are often impaired by supercooling, due to a kinetic delay of the transformation caused by inhibited nucleation. Thus the measured transformation temperature does not necessarily correspond to the thermodynamic equilibrium temperature, but is strongly dependant on the thermal history of the sample and the applied cooling rate. Therefore cooling and heating cycle yield different enthalpy profiles.

The heat flow curve shows two sharp endothermic peaks. One with a peak maximum temperature at -19°C and an extrapolated onset temperature of -21°C, indicating the melting temperature (DSC curve attached).

Conclusions:

The melting temperature of the substance was determined to be -21°C at 1013 hPa using a relevant test method. The result is considered to be reliable.

Description of key information

Freezing point: -21°C (OECD 102)

Key value for chemical safety assessment

Melting / freezing point at 101 325 Pa:

-21 °C

Additional information

A melting temperature value of -21°C at 1013 hPa was determined for the substance using a Differential Scanning Calorimetry (DSC) in accordance with OECD Test Guideline 102 and in compliance with a known quality system (ISO 17025). The result is considered to be reliable and is selected as key study.

In a secondary source to which reliability could not be assigned, melting temperature value of -32°C at 1013 hPa was reported for the substance.