Reaction Mass of 3,3-diphenylhexamethyltrisiloxane and 3,3,5,5-tetraphenylhexamethyltetrasiloxane

Boiling point

Link to relevant study record(s)

Reference

Endpoint:

boiling point

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2004-06-24 to 2004-06-29

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

EU Method A.2 (Boiling Temperature)

Version / remarks:

December 1992

Deviations:

no

Qualifier:

according to guideline

Guideline:

OECD Guideline 103 (Boiling Point/Boiling Range)

Deviations:

no

GLP compliance:

yes

Type of method:

differential scanning calorimetry

Key result

Boiling pt.:

ca. 268 - ca. 342 °C

Atm. press.:

1 013 hPa

Key result

Boiling pt.:

ca. 541 - ca. 615 K

Atm. press.:

1 013 hPa

The DSC-curve of the first run (heating rate of 20 K/min from 25°C to 400°C) is shown in Figure 1 attached. An endothermic heat effect, boiling was observed between 256°C and 345°C. After the experiment, the sample had lost about 95.7% of its mass.

In order to determine the boiling range more precisely, further DSC runs were recorded between about 200°C and 400°C with a heating rate of 10 K/min. In the second run, the boiling range was determined to be between 277.2°C and 346.7°C. During this run, the sample lost 85.6% of its mass. After the measurement, the sample was clear, colourless and liquid.

In the third run, the boiling range was determined to be between 259.1°C and 334.9°C. During this run, the sample lost 94.2% of its mass. The DSC curve of this measurement is given in Figure 2 attached. The sample was unaltered in appearance.

As the temperature of the endothermic effect was not very well reproducible, it can only be calculated that the boiling point will be most probable in the range of about 268°C to 342°C (541 K to 615 K).

The results are summarised in Table 1 below.

Table 1: Determination of the boiling range (summary)

 

Run No.	Heating range [°C]	Heating rate [K/min]	Boiling range [°C]	Boiling range [K]
Pre-test	25 – 400	20	255.9 – 345.1	529.1 – 618.3
2	200 – 400	10	277.2 – 346.7	550.4 – 619.9
3	200 – 400	10	259.1 – 334.9	532.3 – 608.1
Mean boiling range			268.1 – 340.8	541.3 – 615.4

 

The mean boiling range was calculated from the bold values.

Conclusions:

A boiling range of 268°C to 342°C at 1013 hPa was determined for the substance using a relevant test method and in compliance with GLP. The result is considered to be reliable.

Description of key information

Boiling range: 268°C to 342°C at 1013 hPa (OECD 103)

Additional information

A boiling range of 268°C to 342°C at 1013 hPa was determined for the substance using Differential Scanning Calorimetry (DSC) in accordance with OECD Test Guideline 103 and in compliance with GLP. The result is considered to be reliable.