Oligomerisation products of 2,2'-[(1-methylethylidene)bis(4,1-phenyleneoxymethylene)]bisoxirane with acrylic acid and lauric acid

Partition coefficient

Link to relevant study record(s)

Reference

Endpoint:

partition coefficient

Type of information:

experimental study

Adequacy of study:

key study

Study period:

April 15, 2020 to April 16, 2020

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

other: EU A.24- partition coefficient (n-octanol/water), high performance liquid chromatography (HPLC) method

Version / remarks:

2015

Deviations:

no

Qualifier:

according to guideline

Guideline:

OECD Guideline 117 (Partition Coefficient (n-octanol / water), HPLC Method)

Version / remarks:

2004

Deviations:

no

GLP compliance:

not specified

Other quality assurance:

other: SOP 118 009 30 “Bestimmung des log POW (Verteilungskoeffizient n-Octanol/Was- ser) mittels HPLC“, edition 7, adopted 18. Sep. 2017

Type of method:

HPLC method

Partition coefficient type:

octanol-water

Analytical method:

high-performance liquid chromatography

Key result

Type:

log Pow

Partition coefficient:

>= 2.516 - <= 3.513

Temp.:

25 °C

pH:

>= 5 - < 6

Reference substances measurement data:

The retention times which were recorded for the reference substances are presented in the following table.

Retention times (RT) reference substances:

Compound	RT 1	RT 2	RT 3	RT 4	RT 5	RT 6
	min.	min.	min.	min.	min.	min.
Thiourea	1.410	1.407	1.410	1.410	1.407	1.410
2-Butanone	1.730	1.727	1.730	1.727	1.727	1.727
Acetophenone	2.190	2.190	2.193	2.190	2.190	2.190
Naphthalene	5.560	5.580	5.560	5.560	5.557	5.553
Diphenyl ether	7.453	7.483	7.453	7.453	7.453	7.447
Phenanthrene	10.703	10.737	10.703	10.707	10.700	10.697
Fluoranthene	14.937	14.987	14.943	14.947	14.937	14.940
Triphenylamine	26.303	26.373	26.317	26.310	26.307	26.307
4,4’-DDT	37.890	37.953	37.923	37.887	37.880	37.877

 

Reference substance calculated value:

For each reference substance, the calculated capacity factors are presented in the following table.

Capacity factors reference subatance

Compound	Retention Time Mean	Retention Time Standard Deviation	Retention Time Relative Standard Deviation	k
	min.	min.	%
Thiourea	1.409	0.002	0.122	0.0000
2-Butanone	1.728	0.002	0.100	0.2263
Acetophenone	2.191	0.001	0.062	0.5548
Naphthalene	5.562	0.009	0.168	2.9476
Diphenyl ether	7.457	0.013	0.175	4.2930
Phenanthrene	10.708	0.015	0.136	6.6002
Fluoranthene	14.948	0.019	0.128	9.6100
Triphenylamine	26.319	0.027	0.102	17.6810
4,4’-DDT	37.902	0.030	0.080	25.9018

 

log P_OW / log k

The values for log k and log P_OW of the reference items are presented in the following table:

log k and log P_OW of reference substance

Compound	log k	log POW
2-Butanone	-0.6452	0.30
Acetophenone	-0.2559	1.70
Naphthalene	0.4695	3.60
Diphenyl ether	0.6328	4.20
Phenanthrene	0.8196	4.50
Fluoranthene	0.9827	5.10
Triphenylamine	1.2475	5.70
4,4’-DDT	1.4133	6.50

 

Correlation results:

Dead time is 1.409 ± 0.002 minutes, with RSD (relative standard deviation) 0.12%. The RSD of the retention times of the reference items lay all below 0.18 %. Equation of the regression:

log k = 0.3459 * log POW – 0.7831

with a coefficient of determination r2 = 0.9959

 

The chromatogram of the test substance gave three major and eight minor peaks. With the calibration function log k versus log P_OW, the corresponding log P_OW values of the major peaks were determined with:

Peak	Mean Area	Relative Area	Mean Retention Time	Log POW ± Standard Deviation
	[mAU*min]1	[%]	[min]
1	21.002	7.819	3.131	2.516 ± 0.004
2	175.873	65.473	5.219	3.513 ± 0.002
9	40.380	15.032	49.438	> 6.5

These values are the means ± standard deviations of three independent determinations.

 

The peaks 3-8, 10 and 11 showed a relative area <5 %, they were considered as minor peaks. Although area is not necessarily correlated to absolute concentration if a UV detector is used, it is assumed that the test substance consists mainly of the substances eluting as peaks 1, 2 and 9. Using the correlation log k / log POW, the log POW of the major components of test substance without diluting monomer was calculated as 2.516 ± 0.004 – 3.513 ± 0.002 (mean ± standard deviation) at the temperature of 25.0 ± 0.5°C for the substances eluting as peaks 1 and 2. The peak 9 lay with a retention time of 49.438 min over the retention time of DDT (37.902 min), because it could only be eluted from the column with a washing step with 100% pure methanol, added after the elution time of the last eluting reference substance. Peak 9 of the test substance without diluting monomer lay thus outside of the calibrated range, a precise log Pow could not be calculated. Therefore, the log POW of the substance eluting as Peak 9 is stated as > 6.5 (highest log POW of a reference substance (DDT)). To determine the components of the reference substance mix and the test substance solution, different wavelengths were used (254 nm and 228 nm). The wavelength influences the sensitivity of the system (height of the peaks and number of peaks) but does not change the retention time. Since the partition coefficient is determined on the basis of a comparison of the retention time, which is not affected by the use of a different wavelength, the evaluation is considered valid.

 

For measurement data and calculated values of test substance please refer to the attached background material.

Conclusions:

Under the study conditions the log Pow value of the test substance was found to be in a range of 2.516 ± 0.004 - 3.513 ± 0.002.

Executive summary:

The study was performed with the test substance using HPLC with a C18 column in accordance with OECD TG 117 and EU A.24. The log P_OW of the major components of the test substance without diluting monomer was in the range of 2.516 ± 0.004 - 3.513 ± 0.002 (Feierabend, 2020).

Description of key information

The partition coefficient was determined according to OECD Guideline 117 and EU Method A.24 (Feierabend, 2020).

 

Key value for chemical safety assessment

Log Kow (Log Pow):

3.513

at the temperature of:

25 °C

Additional information

Peaks which showed relative area <5% was considered minor peaks and was not considered for the calculation of log Kow. The log kow of the major peaks of the test substance without diluting monomer was in the range of 2.516 - 3.513. One single peak of the test substance without diluting monomer laid outside of the
calibrated range, therefore no log kow could be calculated and hence the log kow of this peak was stated as >6.5 (highest log kow of a reference substance, DDT).