Registration Dossier

Data platform availability banner - registered substances factsheets

Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.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.

Diss Factsheets

Physical & Chemical properties

Partition coefficient

Currently viewing:

Administrative data

Link to relevant study record(s)

Reference
Endpoint:
partition coefficient
Type of information:
experimental study
Adequacy of study:
key study
Study period:
2014-02-06 to 2014-04-23
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study
Qualifier:
according to guideline
Guideline:
OECD Guideline 117 (Partition Coefficient (n-octanol / water), HPLC Method)
Version / remarks:
adopted 27 July 1995
Deviations:
no
GLP compliance:
yes (incl. QA statement)
Type of method:
HPLC method
Partition coefficient type:
octanol-water
Specific details on test material used for the study:
- Name of test material (as cited in study report): Dilactide
- Substance type: solid
- Physical state: White crystals
- Analytical purity: 100%
- Lot/batch No.: 1307003243
- Expiration date of the lot/batch: 01 January 2015
- Stability under test conditions: yes; stock solutions in acetonitrile are stable for at least 7 days. Dilactide is not stable in water due to hydrolysis.
- Storage condition of test material: In freezer (≤-15 °C) in the dark under nitrogen
- Hygroscopic: Yes, store in well-sealed container
Analytical method:
high-performance liquid chromatography
Type:
Pow
Partition coefficient:
2.7
Temp.:
25 °C
Remarks on result:
other: neutral pH
Key result
Type:
log Pow
Partition coefficient:
0.4
Temp.:
25 °C
Remarks on result:
other: neutral pH
Details on results:
Calculation method: Calculation of the Pow
The Pow of the test substance was calculated to be 2.3 (log Pow 0.36) using the Rekker calculation method.

Calculation of the pKa
Dilactide does not contain any acidic or basic groups.

HPLC Method:
In the chromatogram of the test solution, one major peak and one small peak were observed. The results of the HPLC method are given in Table 1 in box " Any other information on results incl. tables. The equation of the regression line was: log k’ = 0.624 = log Pow – 0.387 (r = 0.998, n = 12).

Table 1: log Pow of the test substance and reference substances

Substance

tr,1
[min]

tr,2
[min]

mean tr
(n= 2)

log Pow

Pow

Area
%

 

 

 

 

 

 

 

Formamide (t0)

0.580

0.581

0.581

 

 

 

 

 

 

 

 

 

 

2-Butanone

0.947

0.946

0.947

0.3

 

 

Benzylalcohol

1.823

1.828

1.826

1.1

 

 

Nitrobenzene

3.785

3.787

3.787

1.9

 

 

Toluene

13.079

13.085

13.082

2.7

 

 

Bromobenzene

17.237

17.245

17.241

3.0

 

 

1,4-Dichlorobenzene

33.313

33.332

33.323

3.4

 

 

 

 

 

 

 

 

 

Test substance

1.016

1.021

1.019

0.4

2.7

99.9

Impurity I

1.589

1.586

1.588

1.0

10

0.1

 

 

 

 

 

 

 

Conclusions:
The HPLC method was applied for the determination of the partition coefficient of dilactide. The log Pow at neutral pH was determined to be 0.4.
Executive summary:

The HPLC method in accordance with OECD TG 117, was considered to be the most suitable method to determine the log Pow of dilactide.

The Pow value of dilactide was determined to be 2.7, which corresponds to a log Pow of 0.4 at neutral pH.

Description of key information

The partition coefficient of dilactide was determined to be log Pow = 0.4 using to the HPLC method (OECD 117).

Key value for chemical safety assessment

Log Kow (Log Pow):
0.4
at the temperature of:
25 °C

Additional information