Reaction mass of 2,2'-(vinylenedi-p-phenylene)bis[5-methylbenzoxazole] and 2,2'-(vinylenedi-p- phenylene)bisbenzoxazole and 2-[4-[2-[4-(benzoxazol-2- yl)phenyl]vinyl]phenyl]-5-methylbenzoxazole

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:

February 28, 2018

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:

adopted July 27, 1995

Qualifier:

according to guideline

Guideline:

other: OECD Guideline 113 (Screening Test for Thermal Stability and Stability in Air)

Version / remarks:

adopted May 12, 1981

GLP compliance:

yes (incl. QA statement)

Type of method:

differential scanning calorimetry

Specific details on test material used for the study:

The test item was used in its initial form.

Melting / freezing pt.:

ca. 263.9 - ca. 296.5 °C

Before the test the appearance of the substance was yellow powder; after the experiments the test item became a yellow melt with bubbles and with dark brown trim around the melt.

	Sample weight [mg]	Total loss of Mass of the Sample (%)	Onset of effect [°C]	Endset of effect [°C]	Left Limit [°C]	Right Limit [°C]	Energy [J/g]
Replicate 1	2.66	34.2	264.26	281.09	264.26	296.27	56.60 (endothermic)
Replicate 2	2.40	27.1	273.45	278.83	263.61	296.69	51.73 (endothermic)
Mean					263.94	296.48	54.17 (endothermic)

The test item showed endothermic signal in the temperature range of approx. 240 – 260 °C. In order to determine if this signal associated with melting of any constituent of test item or not, a Supplementary test was performed.

During the first heating, the appearance, consistency and weight of the test item did not change in the crucible. During the cooling phase no thermal effects were observed from 263 to 25 °C. In the second heating, this observed endothermic peak was no longer appeared on the thermogram and during the cooling phase no thermal effects were observed also. Therefore it is concluded that the test item did not melt in the crucible up to 263 °C.

Conclusions:

The substance starts to melt at ca 260 °C.

Executive summary:

The thermal behaviour of the test item was investigated by Differential Scanning Calorimetry method, according to the OECD guidelines 102 and 113. A small amount of test item placed in aluminum cosed crucible and inserted into the furnace of the DSC device. The temperature was increased from 25 to 500 °C with 10 °C/minutes heating rate. The measurement was performed under nitrogen atmosphere. The experiment was performed in duplicate.

A supplementary test was run, in order to clarify the substance thermal behavior. A small amount of test item was placed in aluminum crucible the furnace of the DSC device was heated from 25 to 263 °C with 10 °C/minutes heating rate, than cooled down to 25 °C.

The test item showed endothermic signal in the temperature range of approx. 240 – 260 °C. In order to determine if this signal associated with melting of any constituent of test item or not, a Supplementary test was performed. During the first heating, the appearance, consistency and weight of the test item did not change in the crucible. During the cooling phase no thermal effects were observed from 263 to 25 °C. In the second heating, this observed endothermic peak was no longer appeared on the thermogram and during the cooling phase no thermal effects were observed also. Therefore, it is concluded that the test item did not melt in the crucible up to 263 °C.

Before the test the appearance of the substance was yellow powder; after the experiments the test item became a yellow melt with bubbles and with dark brown trim around the melt.

Applying a linear heating rate, the melting point of test item was determined to be in the range of 263.9 – 296.5 °C (537.1 – 569.6 K).

Conclusion

The substance starts to melt at ca 260 °C.

Description of key information

melting point in the range of 263.9 – 296.5 °C

Key value for chemical safety assessment

Melting / freezing point at 101 325 Pa:

264 °C

Additional information

OECD guideline 102 and 113