Trichloro(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)silane

Vapour pressure

Link to relevant study record(s)

Reference

Endpoint:

vapour pressure

Type of information:

(Q)SAR

Adequacy of study:

key 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:

See attached QMRF/QPRF

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 uses the normal boiling point as input. 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 organosilicon compounds. 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 vapour pressure prediction from MPBPVPWIN as the descriptor. The adapted model applies to organosilicon substances.

Key result

Test no.:

#1

Temp.:

25 °C

Vapour pressure:

30 Pa

Conclusions:

A vapour pressure value of 30 Pa at 25°C has been determined for the substance using an appropriate estimation method. The result is considered to be reliable.

Description of key information

Vapour pressure [2-(perfluorohexyl)ethyl]trichlorosilane]: 30 Pa at 25°C (QSAR)

Vapour pressure [2-(perfluorohexyl)ethyl]silanetriol]: 6.9E-03 Pa at 25°C (QSAR)

Key value for chemical safety assessment

Vapour pressure:

30 Pa

at the temperature of:

25 °C

Additional information

A vapour pressure value of 30 Pa at 25°C was determined for [2-(perfluorohexyl)ethyl]trichlorosilane using a validated QSAR estimation method. The result is considered to be reliable.

 

Under dilute conditions in water, the submission substance hydrolyses very rapidly to form [2-(perfluorohexyl)ethyl]silanetriol and hydrochloric acid. The vapour pressure of the silanol hydrolysis product was predicted to be 6.9E-03 Pa at 25°C using the same validated QSAR estimation method as for the parent.