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Diss Factsheets
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EC number: 617-969-6 | CAS number: 87135-01-1
- Life Cycle description
- Uses advised against
- Endpoint summary
- Appearance / physical state / colour
- Melting point / freezing point
- Boiling point
- Density
- Particle size distribution (Granulometry)
- Vapour pressure
- Partition coefficient
- Water solubility
- Solubility in organic solvents / fat solubility
- Surface tension
- Flash point
- Auto flammability
- Flammability
- Explosiveness
- Oxidising properties
- Oxidation reduction potential
- Stability in organic solvents and identity of relevant degradation products
- Storage stability and reactivity towards container material
- Stability: thermal, sunlight, metals
- pH
- Dissociation constant
- Viscosity
- Additional physico-chemical information
- Additional physico-chemical properties of nanomaterials
- Nanomaterial agglomeration / aggregation
- Nanomaterial crystalline phase
- Nanomaterial crystallite and grain size
- Nanomaterial aspect ratio / shape
- Nanomaterial specific surface area
- Nanomaterial Zeta potential
- Nanomaterial surface chemistry
- Nanomaterial dustiness
- Nanomaterial porosity
- Nanomaterial pour density
- Nanomaterial photocatalytic activity
- Nanomaterial radical formation potential
- Nanomaterial catalytic activity
- Endpoint summary
- Stability
- Biodegradation
- Bioaccumulation
- Transport and distribution
- Environmental data
- Additional information on environmental fate and behaviour
- Ecotoxicological Summary
- Aquatic toxicity
- Endpoint summary
- Short-term toxicity to fish
- Long-term toxicity to fish
- Short-term toxicity to aquatic invertebrates
- Long-term toxicity to aquatic invertebrates
- Toxicity to aquatic algae and cyanobacteria
- Toxicity to aquatic plants other than algae
- Toxicity to microorganisms
- Endocrine disrupter testing in aquatic vertebrates – in vivo
- Toxicity to other aquatic organisms
- Sediment toxicity
- Terrestrial toxicity
- Biological effects monitoring
- Biotransformation and kinetics
- Additional ecotoxological information
- Toxicological Summary
- Toxicokinetics, metabolism and distribution
- Acute Toxicity
- Irritation / corrosion
- Sensitisation
- Repeated dose toxicity
- Genetic toxicity
- Carcinogenicity
- Toxicity to reproduction
- Specific investigations
- Exposure related observations in humans
- Toxic effects on livestock and pets
- Additional toxicological data
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Endpoint summary
Administrative data
Description of key information
Additional information
1,6-Bis(trimethoxysilyl)hexane is a liquid at standard temperature and pressure, with a measured melting point of <-20°C, and a measured boiling point of 294°C. It has a measured density of 1.01 g/cm3 at 25°C, a predicted kinematic viscosity of 5.6 mm2/s at 20°C and a measured vapour pressure of 0.081 Pa at 25°C.
The substance is not classified for flammability according to Regulation (EC) No. 1272/2008, on the basis of a measured flash point of 129°C and a measured boiling point of 294°C. It has a measured auto-ignition temperature of 238°C, and is not explosive and not oxidising on the basis of examination of the chemical structure.
In contact with water 1,6 -bis(trimethoxysilyl)hexane reacts rapidly (half-life 5.2 hours at pH 7, 0.08 hours at pH 5, 0.15 hours at pH 9 and 25°C) to produce 1,6 -bis(trihydroxysilyl)hexane and methanol according to the following equation:
(CH3O)3Si(CH2)6Si(OCH3)3+ 3H2O →(OH)3Si(CH2)6Si(OH)3+ 6CH3OH
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 are assessed instead.
Methanol is miscible with water, has low log Kow (-0.82 to -0.64) and high vapour pressure (12,790 Pa at 20°C) (OECD 2004).
The saturation concentration in water of the silanol hydrolysis product, 1,6-bis(trihydroxysilyl)hexane 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 (-3.5, predicted). It is less volatile than the parent substance (vapour pressure of 1.2E-09 Pa at 25°C, predicted). The first dissociation constant of a structurally analogous silanetriol (phenylsilanetriol) has been reported to be around pKa= 10.
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.
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