4,4'-Isopropylidenediphenol, polymer with 1-chloro-2,3-epoxypropane, propane-1,2-diol acrylate and succinic anhydride

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:

06 May, 2004

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

EU Method A.1 (Melting / Freezing Temperature)

Deviations:

no

Qualifier:

according to guideline

Guideline:

OECD Guideline 102 (Melting point / Melting Range)

Deviations:

no

Principles of method if other than guideline:

The melting temperature of the test substance was evaluated using DSC. This technique records the difference in heat flow to two crucibles, one filled with test substance and the other filled with an inert reference substance, while these crucibles are subjected to a controlled temperature programme. When the test substance undergoes a transition, such as melting or evaporation, this is indicated by a deviation from the base line of the heat-flow record. Because melting and evaporation are processes in which heat is consumed, for these processes the deviation from the base line is in the endothermic direction.

GLP compliance:

yes (incl. QA statement)

Type of method:

other: Differential scanning calorimeter (DSC)

Key result

Decomposition:

yes

Decomp. temp.:

> 200 °C

Remarks on result:

other: Upon heating, the test substance transfers from the glassy state to the (supercooled) liquid state, therefore melting was not observed. The glass transition region and temperature were -22 to -2°C and -14/-13°C, respectively.

Both the test substance and an inert reference were heated in a DSC. The difference between the heat flow to the sample and the heat flow to the reference was recorded. Three experiments were performed. Two experiments were performed starting from 25°C and one experiment was performed starting from -40°C (two runs).

Experiment 1: At about 114°C a very small effect was observed. An exothermic effect was observed above 200°C. This effect is probably caused by reaction or decomposition of the test substance. After the experiment the test substance, which originally was reddish, highly viscous liquid, appeared to have hardened (glassy). The colour had changed to yellow. The change of the colour of the sample is an indication that the test substance had reacted or decomposed. The test substance had lost 1% of its mass.

Experiment 2: A very small effect was observed at about 88°C. A similar effect was observed during the first experiment (at 114°C). Because it is obvious that melting or boiling did not cause this effect, interpretation of the very small effect is outside the scope of this study. An exothermic effect was observed between 200°C and about 345°C. This effect is probably caused by reaction or decomposition of test substance. Above 345°C an endothermic effect was observed, but at these temperatures the test substance had already reacted or decomposed. After the experiment the sample had a dark brown colour. The change of the colour indicates that the test substance had reacted or decomposed. The test substance had lost 33% of its mass.

Experiment 3: During the first run a shift of base line level (into the endothermic direction), in combination with a small endothermic peak, was observed between -22°C and -2°C. During the second run the same effect was observed between -21°C and -2°C. These effects indicate a glass transition (i.e. a transition of a glassy state to supercooled liquid state). The glass transition temperature of the test substance is evaluated as the midpoint (i.e. the temperature at which the curve value is exactly in the middle between the two extrapolated base lines): for the first and the second run -14°C and -13°C, respectively. After the experiment, the consistency of the sample was unchanged and no change of the mass was observed.

Conclusions:

Under the conditions of the study, the substance transfered from the glassy state to the (supercooled) liquid state upon heating, therefore melting was not observed. The glass transition region and temperature were evaluated as -22 to -2°C and -14/-13°C, respectively.

Executive summary:

A study was conducted to evaluate the melting point of the test substance using the differential scanning calorimeter (DSC) method, according to OECD Guideline 102 and EU Method A.1, in compliance with GLP. Both the test substance and an inert reference substance were heated in a DSC. The difference between the heat flow to the sample and the heat flow to the reference was recorded. Three experiments were performed. Two experiments were performed starting from 25°C and one experiment was performed starting from -40°C (two runs). The results of all experiments were combined for the conclusion. The test substance does not crystallize upon cooling, but it forms a glassy state. On heating, the test substance transfers from the glassy state to the (supercooled) liquid state. Melting (i.e. transition from crystalline state to liquid state) is therefore not observed for this test substance. The glass transition region of the test substance was evaluated as -22 to -2°C (251 to 271 K). The glass transition temperature was evaluated as --14/-13°C (259/260 K). Reaction or decomposition of the test substance was observed above 200°C (473 K) (Van der Baan-Treuer, 2004).

Description of key information

The melting point / freezing point was determined using the conventional differential scanning calorimeter (DSC) method according to OECD Guideline 102 and EU Method A.1 (Van der Baan-Treuer 2004).

Additional information

-13/ -14°C (glass transition temperature); reaction or decomposition was observed >200 °C.