Registration Dossier

Physical & Chemical properties

Endpoint summary

Administrative data

Description of key information

Additional information

Undecylenic acid revealed no hazardous phys.-chem. properties, thus no classification.

 Endpoint Result   Comments
 Appearance  Solid  Undecylenic acid is a colourless (white) solid.
 Melting point 21.2-26.4 °C  Melting range is above 20 °C (usual room temperature), thus the substance is not prone to cause exposure to dust and small particles emissions 
Boiling point  286.05- 293.75°C  Relatively high boiling point suggests a generally low fugacity of the substance up to this temperature range
 Density 1.0024  Equals more or less the density of water 
Vapour pressure    0.0192 Pa  Low vapour pressure, what generally suggests that the substance has low potential to cause significant inhalative exposure 
Partition coefficient  log Pow 4.0 

Log Pow 4.0 is in accordance with the low solubility of the substance.

Water solubility   38.46 mg/ l at pH 4.27 and 20°C (lesser solubility at neutral pH)   38.46 mg/l at 20 °C (pH 4.27). Lower solubility in the neutral pH range indicated by another supporting study. Since the water solubility falls within the bracket 0.1 -100 mg/L, undecylenic acid is "slightly soluble".
Flash point   158°C ± 1°C Flash point at relatively high temperatures, no classification as highly flammable. 
Flammability  Not highly flammable  Undecylenic acid is not highly flammable. 
Adsorption coefficient log Koc   

The adsorption coefficient of 10-UNDENECENOIC AClD was found to be log Koc = 2.84 (Koc = 691.83) ( OECD Guideline 121 Adsorption - HPLC) . This result is close to the log Koc 2.77 of reference substance acetanilid, which represents the lower end of adsorbability capacity of the reference substances used. Therefore it is concluded that undecylenic acid has low adsorptive capacity.

 Oxidising properties

 Not oxidising

 Structural assessment indicates that the substance does not have oxidising properties.

 Explosive properties

 Not explosive

 Structural assessment indicates that the substance does not have explosive properties.

 Dissociation constant

 Dissociating propreties.

Undecylenic acid has dissociating properties. However due to its low solubility in water, the acidity constant could not be determined for temperatures lower than 60°C. At 60°C the acidity constant of undecylenic acid is 4.85 (with ionic strentgh : 0.01 mol/L).