Registration Dossier

Physical & Chemical properties

Endpoint summary

Administrative data

Description of key information

Additional information

Tin bis(2-ethylhexanoate) (i.e.,Stannous Octoate) is a clear to pale yellow, viscous liquid at typical ambient temperatures, and is manufactured and used only in this liquid form. The substance does not boil, as thermal decomposition occurs at temperatures above approximately 150 °C in the presence of oxygen. The substance has a relative density of 1.26, which along with its insolubility in water, causes it to sink as a dense non-aqueous phase liquid in aqueous media. Once introduced to water, the substance is known to dissociate into its 2-ethylhexanoate and Sn(II) components. The measured dissociation constant for the intact salt is 5.09, whereas that for the free acid form of 2-ethylhexanoic acid is 4.8. Whereas the Sn(II) component occurs initially in water as Sn(OH)2, this species is expected to spontaneously oxidize in oxygenated water to form the insoluble inorganic solid Sn(IV)O2. The 2 -ethyl hexanoate component has moderate solubility and low octanol-water partition coefficient (log Kow = 2.64). These properties result in a low potential for adsorption to organic matter of soil and sediment. The Tin bis(2-ethylhexanoate) substance exhibits a high flash point (137 °C), and high auto-ignition temperature (> 400 °C), and is therefore regarded as non-flammable liquid. The substance does not possess atoms or functional groups which are known to contribute to pyrophoric or explosive properties, and testing has confirmed the lack of these hazardous properties.