Reaction mass of L-Glutamic acid, N-coco acyl derivs., monosodium salts and sodium hydrogen N-(1-oxooctadecyl)-L-glutamate

Surface tension

Link to relevant study record(s)

Reference

Endpoint:

surface tension

Type of information:

experimental study

Adequacy of study:

key study

Study period:

11 July 2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 115 (Surface Tension of Aqueous Solutions)

Version / remarks:

1995

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method A.5 (Surface Tension)

Version / remarks:

2008

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

ring method

Key result

Surface tension:

29.1 mN/m

Temp.:

20 °C

Remarks on result:

other: Corrected value

A constant surface tension was reached after about 524 sec. Afterwards, four further measurements were performed each after a minimum equilibrium time of 524 sec in order to confirm the value obtained by the first measurement.

The surface tension of the test material aqueous solution read on the instrument was 28.7 mN/m at 20 °C using the ring method representing the mean of five separate measurements. The measured values were corrected with Harkins-Jordan correction factor. The details are shown in Table 1.

The measured surface tension was multiplied by Φb resulting in a corrected surface tension of 29.1 mN/m. As the surface tension value was lower than 60 mN/m, the test material is classified as surface active.

Table 1: Measured surface tension values and equilibrium times.

Surface tension (mN/m)	Time (sec)
28.66	524
28.67	547
28.70	571
28.71	596
28.70	620

 

Conclusions:

Under the conditions of the study the corrected surface tension of the test material was 29.1 mN/m. As the surface tension value was lower than 60 mN/m, the test material is classified as surface active.

Executive summary:

The surface tension of the test material was determined in accordance with the standardised guidelines OECD 115 and EU Method A.5, using the ring method under GLP conditions.

The liquid to be measured was transferred to the measurement vessel. The measurement vessel was placed on the sample table. The sample was raised until the ring is 1 to 2 mm above the surface of the liquid. Then the measurement was started. In order to describe the time dependence of the surface tension after transferring the solution to the measurement vessel, the measurement was continued with increasing equilibrium time until a constant surface tension was reached.

A constant surface tension was reached after about 524 sec. Afterwards, four further measurements were performed each after a minimum equilibrium time of 524 sec in order to confirm the value obtained by the first measurement. The surface tension of the test material aqueous solution read on the instrument was 28.7 mN/m at 20 °C using the ring method representing the mean of five separate measurements. The measured surface tension was multiplied by Φb to give a corrected surface tension.

Under the conditions of the study the corrected surface tension of the test material was 29.1 mN/m. As the surface tension value was lower than 60 mN/m, the test material is classified as surface active.

Description of key information

Under the conditions of the study the corrected surface tension of the test material was 29.1 mN/m. As the surface tension value was lower than 60 mN/m, the test material is classified as surface active.

Key value for chemical safety assessment

Surface tension:

29.1

Additional information

The surface tension of the test material was determined in accordance with the standardised guidelines OECD 115 and EU Method A.5, using the ring method under GLP conditions. The study was awarded a reliability score of 1 in accordance with the criteria set forth by Klimisch et al. (1997).

The liquid to be measured was transferred to the measurement vessel. The measurement vessel was placed on the sample table. The sample was raised until the ring is 1 to 2 mm above the surface of the liquid. Then the measurement was started. In order to describe the time dependence of the surface tension after transferring the solution to the measurement vessel, the measurement was continued with increasing equilibrium time until a constant surface tension was reached.

A constant surface tension was reached after about 524 sec. Afterwards, four further measurements were performed each after a minimum equilibrium time of 524 sec in order to confirm the value obtained by the first measurement. The surface tension of the test material aqueous solution read on the instrument was 28.7 mN/m at 20 °C using the ring method representing the mean of five separate measurements. The measured surface tension was multiplied by Φb to give a corrected surface tension.

Under the conditions of the study the corrected surface tension of the test material was 29.1 mN/m. As the surface tension value was lower than 60 mN/m, the test material is classified as surface active.