3,3,5,7,7-pentamethyl-1,2,4-trioxepane

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

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

GLP compliance:

yes

Type of method:

thermal analysis

Specific details on test material used for the study:

Clear colourless liquid, purity 96.5%.

Key result

Melting / freezing pt.:

>= -25 - <= -21 °C

Decomposition:

no

Sublimation:

no

Remarks on result:

other: The test substance showed a clear transition phase from liquid to solid.

Remarks:

Because the resulting freezing temperature differed more than 1 K, a range is reported. Probably due to undercooling effects. The method is validated periodically using n-octane and water.

Preliminary test:

Temperature range during storing (°C)	Test substance appearance after 1 hour	Test tube turned upside down	Test substance appearance after an additional hour
3.8to 5.3	Clear colour less	No	Clear colour less
-23.5 to -22.9	Turbid	No	Turbid
-82.4 to -81.4	White solid	Yes	White solid, test substance did not flow downwards

Freezing is expected to occur between -82  °C and -23 °C

Main study:determination freezing temp.

The lowest temperatures measured in the four tests were; -16.4, ≤-24.6, -20.8, -25.3. At -16.4 the test substance was still liquid. Therefore this temp. was not used as a freezing temp. 

Conclusions:

Determined the freezing range for pentamethyl-trioxepane from -25 to -21°C

Executive summary:

Determined the freezing range for pentamethyl-trioxepane from -25 to -21°C

Description of key information

Determined the freezing range for pentamethyl-trioxepane from -25 to -21°C

Key value for chemical safety assessment

Melting / freezing point at 101 325 Pa:

-21 °C