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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.

The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.

Diss Factsheets

Physical & Chemical properties

Endpoint summary

Administrative data

Description of key information

1,3,5 -Tris[3-(trimethoxysilyl)propyl]-1,3,5-triazinane-2,4,6-trione is a highly viscous liquid at standard temperature and pressure, with a measured melting point of <-50°C. The substance was observed to undergo thermal decomposition from about 210°C. It has a measured relative density of 1.173 at 20°C, a measured kinematic viscosity of 302 mm2/s at 20°C and a measured vapour pressure of 0.11 Pa at 20°C.

The substance is not classified for flammability in accordance with Regulation (EC) No. 1272/2008 on the basis of a measured flash point of 93.5°C. It has a measured auto-ignition temperature of 350°C at 966 - 970 hPa, and it is not oxidising on the basis of chemical structure.

The substance is considered not explosive under the conditions of an EU Test Method A.14.

In contact with water 1,3,5-tris[3-(trimethoxysilyl)propyl]-1,3,5-triazinane-2,4,6-trione reacts rapidly (half-life of 111.3 minutes at pH 7, 5 minuets at pH 4 and 4.5 minutes at pH 9 and 25°C) to produce 1,3,5-tris[3-(trihydroxysilyl)propyl]-1,3,5-triazinane-2,4,6-trione and methanol according to the following equation:

C21H45N3O12Si3+ 9H2O ¿ C12H27N3O12Si+ 9CH3OH


Therefore, requirements for testing of water-based physicochemical properties for the substance are waived on the basis of instability in water. The properties of the hydrolysis products, 1,3,5-tris[3-(trihydroxysilyl)propyl]-1,3,5-triazinane-2,4,6-trione and methanol are assessed instead.

However, the physicochemical properties of the substance, 1,3,5-tris[3-(trimethoxysilyl)propyl]-1,3,5-triazinane-2,4,6-trione have been predicted using a validated QSAR estimation method. It has a log Kow value of 2.4 at 20°C and water solubility value of 1.4E-02 mg/l at 20°C.

Methanol is miscible with water, has low log Kow (-0.82 to -0.64) and high vapour pressure (12790 Pa at 20°C) (OECD 2004).


The saturation concentration in water of the silanol hydrolysis product, 1,3,5-tris[3-(trihydroxysilyl)propyl]-1,3,5-triazinane-2,4,6-trione is limited by condensation reactions that can occur over time at loadings above approximately 100 mg/l. However, it is very hydrophilic (calculated solubility is 1.0E+06 mg/l at 20°C using a QSAR method) and has a low log Kow (-4.0, predicted). It is not expected to be surface active and is much less volatile than the parent substance with a predicted vapour pressure of <1.0E-06 Pa at 25°C.


OECD (2004). SIDS Initial Assessment Report for SIAM 19, Berlin, Germany, 18 - 20 October 2004, Methanol, CAS 67-56-1


Additional information