Disodium oxybis[methylbenzenesulphonate]

Vapour pressure

Description of key information

Ditolylether disulfonic acid disodium salt, isomer mixture is an UVCB substance consisting of positional isomers of two basic structures [sodium salts of disulfonated and trisulfonated ditolylether]. 
The QSAR determination of the vapour pressure of representative constituents of ditolylether disulfonic acid disodium salt, isomer mixture using the model MPBPWIN included in the Estimation Program Interface (EPI) Suite v4.1 revealed a value of 1.04E-15 Pa at 25 °C for sodium salts of disulfonated ditolylether and 1.17E-18 Pa at 25 °C for sodium salts of trisulfonated ditolylether. The predicted values can be considered reliable yielding a useful result for further assessment.

Key value for chemical safety assessment

Vapour pressure:

0 Pa

at the temperature of:

25 °C

Additional information

The result should be read as 1.04E-15 Pa.

The vapour pressure of ditolylether disulfonic acid disodium salt, isomer mixture was predicted using the Estimation Program Interface (EPI) Suite version 4.1.

Ditolylether disulfonic acid disodium salt, isomer mixture is an UVCB substance consisting of positional isomers of two basic structures which were considered both for calculation [sodium salts of disulfonated and trisulfonated ditolylether].

Since variations in the positions of the substituents have no influence on calculations by the program, the calculations are performed using a representative isomer for each of the basic structures as representative constituents of ditolylether disulfonic acid disodium salt, isomer mixture.

As ditolylether disulfonic acid disodium salt, isomer mixture is a solid, the model uses the melting point and the boiling point for estimation. No melting and boiling point could be experimentally determined, as the sample decomposed at 196°C. Therefore the calculated melting points and boiling points were taken into account for estimation (calculated by MPBPWIN).

The used boiling points are 736°C for sodium salts of disulfonated ditolylether and 831°C for sodium salts of trisulfonated ditolylether. The used melting points are 323° for sodium salts of disulfonated ditolylether and 350°C for sodium salts of trisulfonated ditolylether.

Using the Modified Grain Method the vapour pressure at 25 °C was estimated to be 1.04E-15 Pa for sodium salts of disulfonated ditolylether and 1.17E-18 Pa for sodium salts of trisulfonated ditolylether.

The results for the representative constituents of ditolylether disulfonic acid disodium salt, isomer mixture fall within the applicability domain described above and the applied estimation rules appear appropriate. Regarding the structures, the fragment descriptors used by the program for the estimation of the melting and boiling point are complete.

The predicted values can be considered reliable yielding a useful result for further assessment.