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Physical & Chemical properties

Partition coefficient

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partition coefficient
Type of information:
experimental study
Adequacy of study:
key study
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
test procedure in accordance with national standard methods with acceptable restrictions
according to guideline
other: not specified
Principles of method if other than guideline:
Shake flask method. Concentration of methacrylic acid determined by titration.
GLP compliance:
Type of method:
shake-flask method to: flask method
Partition coefficient type:
Specific details on test material used for the study:
Origin not known, purity typically >= 98 %
Analytical method:
other: acid-base titration
Key result
log Pow
Partition coefficient:
22 °C
ca. 2.2
Details on results:
data according Sangster, J. (1989): 
pH: unspecified, but assumed to be < 2.2 pH of methacrylic acid.
- Hansch and Leo selcted value
- uncertainty: ± 0.20 - pKa = 4.66

No dimerisation in alcohols has been observed by IR-spectroscopy

The experimental value is log Pow=0.93.
Executive summary:

The octanol water partition coefficient was tested in a shake flask method. The concentration of methacrylic acid was measured by titration. The experimental value is log Pow=0.93.

Description of key information

The octanol water partition coefficient was tested in by shake flask method and reported with 0.93 at 22 °C . Based on log Pow bioaccumulation in organisms is not expected.

Key value for chemical safety assessment

Log Kow (Log Pow):
at the temperature of:
22 °C

Additional information

Supporting information is available with calculated values of 0.99 (KOWWIN) and -0.28 (method of Hansch & Leo).