Registration Dossier
Registration Dossier
Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.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.
Use of this information is subject to copyright laws and may require the permission of the owner of the information, as described in the ECHA Legal Notice.
EC number: 242-560-0 | CAS number: 18765-38-3
Partition coefficient
Administrative data
Link to relevant study record(s)
Description of key information
log Kow [tetrakis(2-butoxyethyl) orthosilicate]: 4.3 at 20°C (QSAR)
log Kow [monosilicic acid]:-4 at 20°C (QSAR)
log Kow [2-butoxyethanol]: 0.8
Key value for chemical safety assessment
- Log Kow (Log Pow):
- 4.3
- at the temperature of:
- 20 °C
Additional information
A log Kow value of 4.3 at 20°C was determined for the substance (tetrakis(2-butoxyethyl) orthosilicate) using a QSAR method. The result is considered to be reliable.
Tetrakis(2-butoxyethyl) orthosilicate reacts rapidly with water generating monosilicic acid and 2-butoxyethanol. At concentrations above about 100-150 mg/l (measured as SiO2equivalents), condensation products of monosilicic acid can also form. At concentrations >100-150 mg/l of SiO2, monomeric monosilicic acid condenses into colloidal particles of polysilicic acid (silica sol) or a highly cross-linked network (silica gel). The condensation rate is dependent on temperature, concentration, and acidity/alkalinity (as in the pH) of the system. A dynamic equilibrium is established between monomeric monosilicic acid, oligomers and insoluble amorphous polysilicic acid.
The purpose of the log Kowstudy is to understand the interaction of the substance with water and octanol, which acts as a model for lipids in humans and organisms and for organic carbon in soils and sediments. On the basis of structure and supported by predictions, monosilicic acid has a high affinity with water and low affinity for lipids and organic carbon. A log Kowvalue of -4 was determined for monosilicic acid using a QSAR method. The method has not been validated for inorganic substances but gives an indication of very low log Kow.
2 -Butoxyethanol has a log Kow value of 0.8, based on a median value obtained with available measured experimental data (EU RAR (2006))
EU RAR (2006): European Union Risk Assessment Report, 2-butoxyethanol CAS No.: 111-76-2, Volume 68, 2006.
Information on Registered Substances comes from registration dossiers which have been assigned a registration number. The assignment of a registration number does however not guarantee that the information in the dossier is correct or that the dossier is compliant with Regulation (EC) No 1907/2006 (the REACH Regulation). This information has not been reviewed or verified by the Agency or any other authority. The content is subject to change without prior notice.
Reproduction or further distribution of this information may be subject to copyright protection. Use of the information without obtaining the permission from the owner(s) of the respective information might violate the rights of the owner.
