Alcohols, C9-11, branched and linear, ethoxylated

Surface tension

Link to relevant study record(s)

Reference

Endpoint:

surface tension

Type of information:

experimental study

Adequacy of study:

key study

Study period:

16 Apr-12 July 2012

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

EU Method A.5 (Surface Tension)

GLP compliance:

yes (incl. QA statement)

Type of method:

ring method

Surface tension:

28.5 mN/m

Temp.:

20 °C

Remarks on result:

other: Calibration factor 1.039 (test 2: result accepted); test concentration: 90% of a saturated solution

Measured value of the surface tension of water : 65.5 mN/m

EC standard reading for surface tension of water : 72.75 mN/m

Calibration factor is: 72.75/65.5=1.111

Full test results

Test No	Test Temp (°C)	Solution Age (mins)	Surface Tension Reading (mN/m)	Corrected Value using calibration factor (mN/m)*	Corrected Value for Harkins-Jordan Correction** (mN/m)
1	20	25	41.0	45.5	43.9
2	20	30	40.5	45.0	43.4

The water solubility was taken from the calculated estimate, which was found to be 1.69 – 69.3 mg/L. Therefore a 90 % saturated solution was prepared for the surface tension measurement. Upon the sponsor’s request, testing was repeated to investigate the effect of solution age on the surface tension.

Measured value of the surface tension of water : 70.0 mN/m

EC standard reading for surface tension of water : 72.75 mN/m

Calibration factor is: 72.75/70.0=1.039

Full test results

Test No	Test Temp (°C)	Solution Age (mins)	Surface Tension Reading  (mN/m)	Corrected Value using calibration factor (mN/m)*	Corrected Value for Harkins-Jordan Correction** (mN/m)
1	20	28	29	30.1	28.2
	20	60	29	30.1	28.2
	20	88	29	30.1	28.2
	20	148	29.5	30.7	28.2
2	20	3	29.5	30.7	28.2
	20	15	29	30.1	28.2
	20	30	29	30.1	28.2
	20	50	29	30.1	28.2
	20	65	29	30.1	28.2
	20	75	29	30.1	28.2

*The calibration factor is determined by measuring the Surface Tension of water and comparing the value obtained in literature. ** The corrected value is taken from a table compiled on the basis of the Harkins-Jordan correction. This correction factor is dependent on the dimensions of the measurement ring.

As with the initial test the water solubility was taken from the calculated estimate, which was found to be 1.69 – 69.3 mg/L. A 90 % saturated solution was prepared for the surface tension measurement. 0.11 g of test substance was used to saturate 125 mL of water (Test No 1). After saturation, the solution was allowed to equilibrate for more than 24 hours for aggregations to settle to the surface. The solution was inspected to ensure that no aggregation was sampled for the test solution preparation. 18 mL of aggregate free solution was sampled from near the bottom of the flask and then diluted to 20 mL with water to obtain 90 % saturation.

For Test No 2, 2.47 g of the test material was used for the saturation of 125 mL of water. The same approach was employed as above to prepare the 90% saturated solution for Test No 2.

Description of key information

28.5 mN/m at 20 °C (EU Method A.5, ring method)

Key value for chemical safety assessment

Surface tension:

28.5

Additional information

The surface tension of the substance was determined according to EU method A.5 (ring method). The concentration of the test solution was 90% of the saturation concentration in water.