Hexamethylene diisocyanate, oligomers, reaction products with 3-methoxypropylamine

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:

July 17, 2002

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:

yes

Type of method:

differential scanning calorimetry

Specific details on test material used for the study:

CAS No.: 162492-07-1; Batch No.: lab; Purity: unknown by the sponsor, treated as 100% pure; Appearance: white to off-white solid

Key result

Melting / freezing pt.:

131 - 157 °C

Atm. press.:

1 013 hPa

Decomposition:

yes

Remarks:

substance reacts or decomposes

Decomp. temp.:

175 °C

Sublimation:

no

Because of the complex behaviour of the test substance a simple melting point of the test substance cannot be indicated. it is clear that, after having been heated to 135 °C, the test substance does not visually appear to have been molten, while the test substance does appear to have been molten after having been heated to 180 °C. Therefore it may be concluded that the endothermic effect which shows a maximum at 153 °C — 157 °C is caused by the melting process; the maximum of the endothermic effect is assumed to indicate the end of the melting process. The endothermic and the exothermic effects that precede this melting effect, however, may be caused by a melting and successive recrystallisation if the original test substance is in a metastable crystal structure. Above about 175 °C the test substance reacts or decomposes.

Conclusions:

Under the study conditions, melting of the test substance was observed in the range of 131 °C — 157 °C. The effects that were observed in the temperature range 110 °C — 135 °C may be caused by melting and successive recrystallisation if the original test substance is in a metastable crystal structure. Above 175 °C the test substance reacts or decomposes.

Executive summary:

A study was conducted to determine the melting point of the test substance according to OECD Guideline 102 and EU Method A.1, in compliance with GLP. Both the test substance and an inert reference were heated in a differential scanning calorimeter (DSC). The difference between the heat flow to the sample and the heat flow to the reference was recorded. Five experiments were performed. Under the study conditions, melting of the test substance was observed in the range of 131 °C — 157 °C. The effects that were observed in the temperature range 110 °C — 135 °C may be caused by melting and successive recrystallisation if the original test substance is in a metastable crystal structure. Above 175 °C the test substance reacts or decomposes (van Rijsbergen, 2002).

Description of key information

The melting point was determined according to OECD Guideline 102 and EU Method A.1 (van Rijsbergen, 2002).

Key value for chemical safety assessment

Melting / freezing point at 101 325 Pa:

157 °C

Additional information

Range of 131 °C — 157 °C