Triboron trimethyl hexaoxide

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:

31 October 2017 to 19 December 2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 102 (Melting point / Melting Range)

Qualifier:

according to guideline

Guideline:

EU Method A.1 (Melting / Freezing Temperature)

Qualifier:

according to guideline

Guideline:

EPA OPPTS 830.7200 (Melting Point / Melting Range)

GLP compliance:

yes (incl. QA statement)

Type of method:

differential scanning calorimetry

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: Sponsor and 10037-115-5
- Expiration date of the lot/batch: 06 June 2019
- Purity test date: 06 June 2017

Key result

Atm. press.:

ca. 1 atm

Decomposition:

no

Sublimation:

no

Remarks on result:

other: glass transition occurs upon cooling at -57.1 celsius

8.4.1. Preliminary Test

The TGA curve of the test item is shown in Figure 1 (attached).  Starting at 50°C, the weight of the

sample decreased significantly.  

After the experiment, a dark grey residue remained in the sample container (original colour:

colourless).  The change of the colour indicated reaction and/or decomposition of the test

item.

8.4.2. Main Study

The DSC curve obtained with Experiment 1 is shown in Figure 2 (attached).  During cooling, a glass

transition was observed between -80°C and -40°C (results are archived in the raw data).

During cooling a glass transition was observed between -75°C and -25°C.  The inflection

point of the glass transition was -56.885°C.  An endothermic peak was observed between 0°C

and 175°C.  The endothermic effect was most likely obtained due to evaporation of volatile

components and reaction and/or decomposition of the test item.  An endothermic peak was

observed starting at 375°C.  The endothermic effect was due to reaction and/or

decomposition of the test item.

After the experiment, a colourless solid residue remained in the sample container.

Experiment 2 was performed as a duplicate of the glass transition temperature.  Figure 3 (attached)

shows the DSC curve obtained.  The inflection point of the glass transition -57.341°C.  After

the experiment, the sample appeared to have been unchanged, i.e. no decomposition and/or

evaporation were observed.  

The glass transition temperature was determined as the mean glass transition temperature of

Experiment 1 (-56.885°C) and Experiment 2 (-57.341°C).

Conclusions:

The melting temperature of Trimethoxyboroxine (TMBX) were determined by DSC.
No melting point was determined. A glass transition of the test item was observed at -57.1°C (216.0K).

Description of key information

The melting temperature of Trimethoxyboroxine (TMBX) were determined by DSC.

No melting point was determined.  A glass transition of the test item was observed at -57.1°C (216.0K).

Key value for chemical safety assessment

Melting / freezing point at 101 325 Pa:

216 K