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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.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

[3-(2,3-Epoxypropoxy)propyl]triethoxysilane is a liquid at standard temperature and pressure, with a measured melting point of <-70°C at 1013 hPa and a predicted boiling point of 270°C at 1013 hPa. It has a predicted density of 0.97 g/cm3 at 20°C, a predicted vapour pressure of 0.07 Pa at 25°C and a predicted kinematic viscosity of 2.3 mm2/s at 20°C.

The substance is soluble in water based on predicted water solubility of 3300 mg/L at 20°C and a predicted log Kow of 2.0.

The substance is not classified for flammability according to Regulation EC (No) 1272/2008 on the basis of a measured flash point of 119°C at 1013 hPa and a predicted boiling point of 270°C at 1013 hPa. It has a measured auto-ignition temperature of 230°C at 1002.1-1019.8 hPa and is not oxidising on the basis of chemical structure. The substance is found not to be explosive based on read-across from related structural analogue, [3-(2,3-epoxypropoxy)propyl]trimethoxysilane using EU Method A.14 test method; the presence of an epoxy group in an organosilicon compound is not associated with explosive properties.

In contact with water, [3-(2,3-epoxypropoxy)propyl]triethoxysilane reacts moderately rapidly (half-life of 12–36 hours at pH 7 and 25°C) to ultimately produce 2,3-dihydroxypropoxypropylsilanetriol and ethanol according to the following equation:

(C2H3O)CH2OCH2CH2CH2Si(OCH2CH3)3 + 4H2O → (CH2OH-CHOHCH2O)CH2OCH2CH2CH2Si(OH)3 + 3CH3CH2OH

Ethanol is miscible with water, has low log Kow of -0.3 and high vapour pressure of 7910 Pa at 25°C.

The saturation concentration in water of the silanol hydrolysis product, 2,3-dihydroxypropoxypropylsilanetriol is limited by condensation reactions that can occur over time at loadings about 1000 mg/L. However, it is very hydrophilic (calculated solubility is 1.0E+6 mg/L at 20°C using a QSAR method) and has a low log Kow of -3.8 (predicted).

The silanol hydrolysis product is not expected to undergo significant dissociation within the environmentally-relevant range. The first dissociation constant of a structurally analogous silanetriol (phenylsilanetriol) has been reported to be around pKa of 10. 2,3-Dihydroxypropoxypropylsilanetriol is much less volatile than the parent substance with a predicted vapour pressure of 1.7E-07 Pa at 25°C and it is not surface active.

Additional information