Registration Dossier

Data platform availability banner - registered substances factsheets

Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.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

Additional information

Physicochemical properties

 

Methyl-N-[3-(trimethoxysilyl)propyl]carbamate is a liquid at standard temperature and pressure. The melting point is <-50°C and the boiling point is 258°C. It has a predicted density of 1.03 g/cm3 at 20°C, a predicted vapour pressure of 0.06 Pa at 20°C and a viscosity of 2.9  mm2/s.

 

The substance is classified as a non-flammable liquid on the basis of the boiling point and a measured flash point of 99°C. It is not pyrophoric or flammable in contact with water. It has a measured self-ignition temperature of 385°C, and is not explosive and not oxidising on the basis of chemical structure. It is not surface active.

 

The substance has a two-step hydrolysis. The rate of formation of the first hydrolysis product, methyl-N-[3-(trihydroxysilyl)propyl]carbamate is relatively fast (half-life 3hours at room temperature and pH 7. However, the rate of formation of the ultimate hydrolysis products, (3-aminopropyl)silanetriol plus methanol and CO2, is extremely slow. Hydrolysis rates (half-life, 25°C, pH 7) of carbamates is reported to vary from a few seconds to 105 years. Therefore only the properties of the first hydrolysis product are described in this summary.

 

(CH3O)3SiCH2CH2CH2N(C=O)OCH3 + 3H2O   (HO)3SiCH2CH2CH2N(C=O)OCH3   + 3CH3OH

 

The silanol hydrolysis product is predicted to be very soluble in water at 20-25°C (1E+06 mg/l) and has a predicted log Kow of -2.3. It is less volatile than the parent substance with a vapour pressure of 9.94E-06 at 25°C (predicted).

 

Methanol is miscible with water, has low log Kow (-0.82 to -0.64) and high vapour pressure, 12.790 Pa at 20°C.

 

Silanetriols may undergo condensation reactions to give siloxane dimers, oligomers and polymers, according to the scheme:

 

RSi(OH)3    RSi(OH)2OSi(OH)2R     RSi(OH)2O[Si(R)(OH)O]nSi(OH)2R

 

(where R is an alkyl or aryl side-chain)

 

A highly cross-linked gel may form. The degree of condensation that will occur may vary with:

 

Concentration of the silanol; the greater the initial concentration, the greater the degree of condensation. Significant condensation is not expected at concentrations less than approximately 100 mg/l, but is dependent on specific conditions.

pH; the condensation reaction may be either acid or base catalysed.

Temperature.

Other species present.  

The nature of the R group

The number of Si-OH groups; silanetriols condense more rapidly than silanediols.