Reaction mass of 1,3-dimethyl-1,1,3,3-tetraphenyldisiloxane and 1,3,3,5-tetramethyl-1,1,5,5-tetraphenyltrisiloxane and 1,3,3,5,5,7-hexamethyl-1,1,7,7-tetraphenyltetrasiloxane

Surface tension

Link to relevant study record(s)

Reference

Endpoint:

surface tension

Type of information:

experimental study

Adequacy of study:

key study

Study period:

October-November 2018

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)

Qualifier:

according to guideline

Guideline:

EU Method A.5 (Surface Tension)

GLP compliance:

yes (incl. QA statement)

Type of method:

plate method

Key result

Surface tension:

72.56 mN/m

Temp.:

19.9 °C

Conc.:

366.7 µg/L

In the main test the test item solution was held at constant temperature (20.0 ± 0.1 °C). 65 minutes after conclusion of the first measurement series, a second measurement series was performed for verification purposes.

During the specified period of time, no significant changes in the surface tension were detected. Values ranging from 72.43 mN/m to 72.74 mN/m were recorded showing no significant variations. The values of the single determinations show no significant difference (less than 5 % (0.07 %) between mean values of the two measurement series)

Conclusions:

The surface tension of an aqueous solution of the test item is higher than 60 mN/m, therfore it is classified as not surface active.

Executive summary:

The surface tension of an aqueous solution of the test item was determined according to OECD 115 resp. EU A.5.

The values of the single determinations show no significant difference (0.07 % between mean values of the two measurement series). All measured values lay clearly above the threshold for surface tension which is stated in the guidelines.

The surface tension of the negative control was determined with a difference of 0.16 % from the stated literature value.

Therefore, the result of the test is considered valid and the test item is classified as “not surface active” in a concentration of 366.7 µg/L (in a solution at 90% saturation obtained from an aqueous solution prepared with 1.00 g/L of test item slow-shaking at 100 rpm for 72 h at 19.7 – 21.7 °C in standing position).

Description of key information

The surface tension of an aqueous solution of the test item was determined according to OECD 115 resp. EU A.5.

The surface tension of an aqueous solution of the test item was determined as 72.56 ± 0.07 mN/m at 19.9 °C. One measurement was performed for verification. No significant changes and thus no significant dependence on time were observed.

The concentration of the test item in the 90% saturated test solution was determined with 366.7 µg test item/L. The saturated solution was obtained from an aqueous solution prepared with 1.00 g/L of test item slow-shaking at 100 rpm for 72 h at 19.7 – 21.7 °C in standing position.

The surface tension of an aqueous solution of the test item is higher than 60 mN/m, therfore it is classified as not surface active.

Key value for chemical safety assessment

Surface tension:

72.56

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

0.367