Diallyl 2,2'-oxydiethyl dicarbonate

Surface tension

Link to relevant study record(s)

Reference

Endpoint:

surface tension

Type of information:

experimental study

Adequacy of study:

key study

Study period:

01 FEB 2010 - 10 MAR 2010

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

EU Method A.5 (Surface Tension)

Version / remarks:

The surface tension result was not corrected using the Harkins-Jordan correction table as the correction is not applicable to the apparatus used. Once calibrated, the balance and ring assembly used in this test give a direct reading for surface tension that is within the required accuracy (± 0.5 mN/m); this is as a result of the reduced ring dimensions. This deviation has been considered not to have affected the integrity of the study.

Deviations:

yes

Remarks:

please refer to 'Version/Remarks'

GLP compliance:

yes (incl. QA statement)

Remarks:

Harlan Laboratories Ltd., Derbyshire, UK

Type of method:

ring method

Surface tension:

57 mN/m

Temp.:

21.8 °C

Conc.:

1.25 g/L

1. Sample solution concentration

The mean peak areas relating to the standard and sample solutions are shown in the following table:

Solution	MeanArea
Standard 8.03 mg/l	5.255 x 10^5
Standard 8.00mg/l	5.130 x 10^5
Matrix blank	none detected
Sample	3.347 x 10^5
Sample solution concentration = 1.25 g/l

2. Calibration factor

The readings, temperatures and the corresponding calibration factors for glass double-distilled water are shown in the following table:

Reading (mN/m)	Temperature (ºC)	Literature Value (mN/m)	Calibration Factor
72.0	21.8	72.44	1.006
72.5	21.8	72.44	0.999
72.5	21.8	72.44	0.999
72.5	21.8	72.44	0.999
72.5	21.8	72.44	0.999
72.0	21.8	72.44	1.006
72.5	21.8	72.44	0.999
Mean of last six Calibration Factors = 1.000

3. Sample solution readings

The readings, times and temperatures for the sample solution are shown in the following table:

Time (mins)	Reading (mN/m)	Temperature (ºC)
73	54.5	21.8
99	57.0	21.8
105	57.0	21.8
112	57.0	21.8
118	57.0	21.8
125	57.0	21.8

Mean of the last six readings: 57.0 mN/m
Surface tension   =  reading x calibration factor
                           =     57.0  x  1.000
                           =     57.0 mN/m
Temperature: 21.8 ± 0.5ºC
pH of sample solution: 5.82

4. Validation

The linearity of the detector response with respect to concentration was assessed over the nominal concentration range of 0 to 15.0 mg/l. This was satisfactory with a correlation coefficient of 0.999 being obtained.

5. Discussion

The water solubility of the test material was determined to be 2.36 g/l at 20.0 ± 0.5°C in Harlan Laboratories Ltd project number 2246/0091. Based on this information, the surface tension of a 1 g/l solution of the test material was attempted. The value obtained (54.4 mN/m) indicated that the test material should be regarded as weak surface active since the value is slightly less than 60 mN/m. However, the absence of a typical surfactant structure (polar head with carbon chain) in addition to the absence of emulsification properties indicated that the test material should not be considered as surface-active.

The water solubility determination (in project number 2246/0091) involved shaking the test material at a loading rate concentration of approximately 10g/L prior to obtaining the saturated solution for analysis. To ensure consistency, the surface tension test was repeated on a 90% saturated solution of the test material, loaded at 10 g/l.

The 90% saturated solution was also diluted to half its concentration and an assessment of surface tension made. This decision was taken based on the expectation of obtaining a concentration of approximately 2 g/l in the 90 % saturated solution and thus the dilution was expected to result in an approximate 1 g/l solution (as specified in the test guideline). However, since the resulting concentration of this solution was significantly less than 1 g/l, the surface tension determination was considered not to be relevant.

The 90% saturated solution was determined to have a concentration of 1.25 g/l which is a lower value than that expected from a solubility of 2.36 g/l. However, a shaking time of only 3 hours was used in the preparation of the 90% saturated solution as compared to a shaking time of at least 24 hours in the solubility determination.

The surface tension value for the 1.25 g/l (90% saturated) solution of 57.0 mN/m was higher than that determined for the 1g/l determination (54.4 mN/m). The lower value for the 1g/l solution probably resulted from interference from insoluble impurities in the solution.

The surface tension value of 57.0 mN/m for the 1.25 g/l solution indicated that the test material can be regarded as being weakly surface-active by Method A5, since it is slightly less than 60 mN/m. However, it was considered that this value was not low enough to solely designate the material surface-active, especially since the test material does not have a typical surfactant structure (polar head with carbon chain). An assessment of the emulsification properties of the test material was also carried out with the test material prepared in water saturated n-octanol and partitioned with an equal amount of n-octanol saturated water. Observations after this test showed that the two immiscible phases separated fully and no emulsification was observed. The absence of emulsification indicated that the test material does not have significant surface active properties.

Conclusions:

The surface tension of a 1.25 g/l solution of the test material was determined to be 57.0 mN/m at 21.8 ± 0.5°C. The test material is considered to be a weak surface-active material by definition of Method A5 since the value is slightly less than 60 mN/m. However, it was considered that this value was not low enough to solely designate the test material surface active based on the lack of surfactant structure and emulsification potential in n-octanol and water.

Executive summary:

The surface tension of the test material was determined using a ring method based on ISO 304, Method A.5 Surface Tension of Commission Regulation (EC) No 440/2008 of 30 May 2008.

The surface tension of the sample solution was measured at intervals until a constant reading was obtained. The elapsed time from transferral to the measuring vessel to obtaining each surface tension reading was recorded. A calibration reading of glass double-distilled water was taken with each sample reading. Readings were taken of the minimum force required to detach the ring from the surface of the liquid. Temperature readings were taken directly after each sample and calibration reading.

The concentration of test material in the sample solution was determined by high performance liquid chromatography and mass spectroscopy (HPLC-MS).

The surface tension of a 1.25 g/l solution of test material was determined to be 57.0 mN/m at 21.8 ± 0.5°C. The test material is considered to be a weak surface-active material by definition of Method A.5 since the value is slightly less than 60 mN/m. However, it was considered that this value was not low enough to solely designate the test material surface active based on the lack of surfactant structure and emulsification potential in n-octanol and water.

Description of key information

The surface tension of the test material was determined using a ring method based on ISO 304, Method A.5 Surface Tension of Commission Regulation (EC) No 440/2008 of 30 May 2008.

The surface tension of the sample solution was measured at intervals until a constant reading was obtained. The elapsed time from transferral to the measuring vessel to obtaining each surface tension reading was recorded. A calibration reading of glass double-distilled water was taken with each sample reading. Readings were taken of the minimum force required to detach the ring from the surface of the liquid. Temperature readings were taken directly after each sample and calibration reading.

The concentration of test material in the sample solution was determined by high performance liquid chromatography and mass spectroscopy (HPLC-MS).

The surface tension of a 1.25 g/l solution of test material was determined to be 57.0 mN/m at 21.8 ± 0.5°C. The test material is considered to be a weak surface-active material by definition of Method A.5 since the value is slightly less than 60 mN/m. However, it was considered that this value was not low enough to solely designate the test material surface active based on the lack of surfactant structure and emulsification potential in n-octanol and water.

Key value for chemical safety assessment

Surface tension:

57

in mN/m at 20°C and concentration in mg/L:

1 250