Magnesium metaborate

Boiling point

Link to relevant study record(s)

Reference

Endpoint:

boiling point

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2016-07-29 - 2017-09-22

Reliability:

1 (reliable without restriction)

Reason / purpose for cross-reference:

reference to same study

Reason / purpose for cross-reference:

reference to same study

Reason / purpose for cross-reference:

reference to same study

Reason / purpose for cross-reference:

reference to same study

Qualifier:

according to guideline

Guideline:

EU Method A.2 (Boiling Temperature)

Version / remarks:

30 May 2008

Deviations:

no

Qualifier:

according to guideline

Guideline:

OECD Guideline 103 (Boiling Point)

Version / remarks:

27 July 1995

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

The Department of Health of the Government of the United Kingdom

Type of method:

differential scanning calorimetry

Key result

Atm. press.:

>= 100 - <= 101 kPa

Decomposition:

yes

Decomp. temp.:

162 °C

Remarks on result:

other: see 'Remarks'

Remarks:

Onset of partial volatilization

Results

Thermographic data for Determinations 1 to 3 are shown in the following table:

Thermal Event	Interpretation	Temerature (°C)
		Determination 1	Determination 2	Determination 3
Endotherm	Onset of partial volatilization	167	163	162

Atmospheric pressure : 100 to 101 kPa

Overall result: partial volatilization from approximately 162 °C (435 K)

Discussion

The test item apparently underwent a complex thermal event from approximately 162°C to just over 300 °C. A weight lost was observed up to 300 °C so this thermal event is probably a partial volatilization. Due to the complex composition of the test item, it was not possible to definitively determine what was occurring during this thermal event. The uneven baseline during the event could suggest decomposition was occurring, however, it could also be that volatilization occurred randomly as the volatiles broke free of the viscous liquid.

Determinations of the mineral oil were also performed. These displayed no distinct thermal event over the range 160 to 300 °C and only a small percentage of the mineral oil was lost after being heated to 300 °C. Therefore, it is unlikely that the thermal event from 160 to just over 300 °C was due to the mineral oil. From approximately 300 to 400 °C the mineral oil was observed to boil by way of a broad endotherm with at least an approximately 80% loss by 400 °C.

The difference in appearance of the test item’s residue after being heated to 300 °C and 400 °C, a viscous liquid and solid respectively, was attributed to the possible loss of the mineral oil that maintained the mobility of the test item. Loss of this caused it to become much more viscous to the point of being a solid.

It was not possible to measure the boiling point of the active ingredient alone, therefore the test item as a whole had to be considered.

Conclusions:

The test item has been determined to partially boil from approximately 162 °C (435 K) at 100 to 101 kPa. It was not possible to definitively assess if any decomposition occurred.

Executive summary:

Partial boiling from approximately 162 °C (435 K) at 100 to 101 kPa by differential scanning calorimetry, designed to be compatible with Method A.2 Boiling Temperature of Commission Regulation (EC) No 440/2008 of 30 May 2008 and Method 103 of the OECD Guidelines for Testing of Chemicals, 27 July 1995.

It was not possible to definitively assess if any decomposition occurred.

Description of key information

Partial boiling from approximately 162 °C (435 K) at 100 to 101 kPa by differential scanning calorimetry, designed to be compatible with Method A.2 Boiling Temperature of Commission Regulation (EC) No 440/2008 of 30 May 2008 and Method 103 of the OECD Guidelines for Testing of Chemicals, 27 July 1995.

It was not possible to definitively assess if any decomposition occurred.

Key value for chemical safety assessment

Boiling point at 101 325 Pa:

162 °C

Additional information

The test item apparently underwent a complex thermal event from approximately 162°C to just over 300 °C. A weight lost was observed up to 300 °C so this thermal event is probably a partial volatilization. Due to the complex composition of the test item, it was not possible to definitively determine what was occurring during this thermal event. The uneven baseline during the event could suggest decomposition was occurring, however, it could also be that volatilization occurred randomly as the volatiles broke free of the viscous liquid.