2,4,6,8-tetramethyl-2,4,6,8-tetravinylcyclotetrasiloxane

Boiling point

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

boiling point

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

other: The result is sourced from secondary literature (publication). No further information is available.

Principles of method if other than guideline:

Information on method and guideline not stated.

GLP compliance:

not specified

Boiling pt.:

224 - 224.5 °C

Atm. press.:

758 mm Hg

Boiling pt.:

111 - 112 °C

Atm. press.:

10 mm Hg

Conclusions:

A boiling point of 224-224.5°C at 758 mmHg was reported in a secondary source. The original reference was not available for review and no further information is available. The reliability of this result is not assignable.

Reference 2

Endpoint:

boiling point

Type of information:

(Q)SAR

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

results derived from a valid (Q)SAR model and falling into its applicability domain, with adequate and reliable documentation / justification

Justification for type of information:

Please refer to attached justification documents

Principles of method if other than guideline:

The result was obtained using an appropriate QSAR method (see attached QMRF and QPRF for details).

The model is an adaptation of the existing SRC model MPBPVPWIN v 1.43, which is a component of the EPI Suite. This existing model is based on fragment values. That is, the chemical structure is broken down into its constituent functional groups, and the contribution of each group toward the overall boiling point is calculated. Certain correction factors may also apply. Whilst this method is good in principle, the model was developed using a wide range of organic chemicals and only a few organosilicon compounds. Therefore, a validation procedure was undertaken to assess the applicability of the model to other organosilicon compounds excluding chlorosilanes and alkoxysilanes. It was noted that the MBBPVPWIN model gave a systematic error; therefore, the current model was developed to correct this. The current model is a linear regression based QSAR, with the boiling point prediction from MPBPVPWIN as the descriptor. The adapted model applies to other organosilanes except chlorosilanes and alkoxysilanes.

Boiling pt.:

220 °C

Atm. press.:

1 013 hPa

Boiling pt.:

496 K

Atm. press.:

1 013 hPa

Conclusions:

A boiling point value of 220°C was obtained using an accepted calculation method. The result is considered to be reliable.

Reference 3

Endpoint:

boiling point

Type of information:

(Q)SAR

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

results derived from a valid (Q)SAR model and falling into its applicability domain, with adequate and reliable documentation / justification

Justification for type of information:

Please refer to attached justification documents

Principles of method if other than guideline:

The result was obtained using an appropriate QSAR method (see attached QMRF and QPRF for details).

Boiling pt.:

ca. 170 °C

Atm. press.:

1 013 hPa

Boiling pt.:

444 K

Atm. press.:

1 013 hPa

Conclusions:

A boiling point value of approximately 170°C was obtained for impurity 2 using an accepted calculation method. The result is considered to be reliable.

Reference 4

Endpoint:

boiling point

Type of information:

(Q)SAR

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

results derived from a valid (Q)SAR model and falling into its applicability domain, with adequate and reliable documentation / justification

Justification for type of information:

Please refer to attached justification documents

Principles of method if other than guideline:

The result was obtained using an appropriate QSAR method (see attached QMRF and QPRF for details).

Boiling pt.:

ca. 270 °C

Atm. press.:

1 013 hPa

Boiling pt.:

540 K

Atm. press.:

1 013 hPa

Conclusions:

A boiling point value of approximately 270°C was obtained for impurity 1 using an accepted calculation method. The result is considered to be reliable.

Description of key information

Boiling point (2,4,6,8-tetramethyl-2,4,6,8-tetravinylcyclotetrasiloxane): 220°C (QSAR)

Key value for chemical safety assessment

Boiling point at 101 325 Pa:

220 °C

Additional information

A predicted boiling point of 220°C was determined for the registered substance, Vi4-D4, using a validated QSAR estimation method. The predicted value is supported by a measured boiling point value of 216.6 - 226.5°C at 1009 ± 1 hPa determined for the low purity form of the registration substance using a Differential Scanning Calorimetry (DSC) method in accordance with OECD Test Guideline 103 and in compliance with GLP. The predicted and measured values are in good agreement; the predicted value is selected as the key value for Chemical Safety Assessment.

This conclusion is supported by boiling point of 224 -224.5°C at 758 mmHg and 111 -112°C at 10 mmHg which was reported for Vi4-D4 in a secondary source to which no reliability could be assigned.

2,4,6,8,10 -Pentamethyl-2,4,6,8,10-pentavinylcyclopentasiloxane Vi5-D5 (CAS No: 17704-22-2; impurity 1) and 2,4,6-trimethyl-2,4,6-trivinylcyclotrisiloxane Vi3-D3 (CAS No: 3901-77-7; impurity 2) may be present as impurities. The boiling points of the impurities have been predicted using a validated QSAR estimation method. Boiling points of approximately 270°C and 170°C were predicted for Vi5-D5 and Vi3-D3 respectively.