Registration Dossier

Diss Factsheets

Physical & Chemical properties

Vapour pressure

Currently viewing:

Administrative data

Link to relevant study record(s)

Description of key information

The vapour pressure of 2,4-TDI is between 0.014hPa and 0.021 hPa at 20° C.

Key value for chemical safety assessment

Additional information

As the ambient vapour pressure of TDI is low, it falls around the lower limit of static measurement methods, and thus the measurement used by Fisk and Langner, giving a value of 0.021hPa, was not entirely appropriate. The gas saturation method used in the Frensdorff and Adams work, giving a value of 0.014hPa. was an appropriate method. The modified Watson calculation also carried out in the Fisk and Langner study gave a similar value, 0.015hPa. These studies have been considered as giving a range for the value of the vapour pressure of 2,4-TDI.

The Bayer study which gave a value of 0.054hPa allowed insufficient pumping time to remove the volatiles.