N-(2-{[C16-18 (even numbered) alkanoyl]amino}ethyl)-N-(2-hydroxyethyl)[C16-18 (even numbered) alkylamide

Surface tension

Link to relevant study record(s)

Reference

Endpoint:

surface tension

Type of information:

experimental study

Adequacy of study:

key study

Study period:

19 July 2017 - 01 June 2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

Study was conducted in accordance with international guidelines and in accordance with GLP. All guideline validity criteria were met.

Qualifier:

according to guideline

Guideline:

EU Method A.5 (Surface Tension)

Version / remarks:

Regulation (EC) 440/2008 of 30 May 2008

Deviations:

no

Qualifier:

according to guideline

Guideline:

OECD Guideline 115 (Surface Tension of Aqueous Solutions)

Version / remarks:

27 July 1995

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

ring method

Key result

Surface tension:

65.8 mN/m

Temp.:

21.9 °C

Remarks on result:

other: Mean Value

Remarks:

Mean Value arising from mean value for Test 1 and mean value for Test 2

Surface tension:

67 mN/m

Temp.:

22 °C

Remarks on result:

other: Test 1

Remarks:

Mean value (last 5 readings)

Surface tension:

64.5 mN/m

Temp.:

21.8 °C

Remarks on result:

other: Test 2

Remarks:

Mean value (last 5 readings)

Evaluation of Data:

In order to determine the surface tension, the mean sample solution reading was calculated from those values obtained that were considered to be on a plateau. The surface tension is given in mN/m (SI sub-unit).

 

 

Results:

The readings, times and temperatures for the sample solutions are shown in the following tables:

 

Table 2:          Surface Tension Measurement, Sample 1

Time (mins)	Reading (mN/m)	Temperature (°C)
68	63.5	22.0
80	65.0	22.0
93	65.5	22.0
106	66.0	22.0
120	66.0	22.0
133	67.0	22.0
154	67.0	22.0
168	67.0	22.0
180	67.0	22.0
192	67.0	22.0

Mean Sample 1 result (last 5 readings): 67.0 mN/m

Mean temperature (last 5 readings): 22.0 °C

pH of Sample 1: 6.3

 

 

Table 3:          Surface Tension Measurement, Sample 2

Time (mins)	Reading (mN/m)	Temperature (°C)
970	55.0	21.6
985	58.5	21.6
1007	60.5	21.6
1023	62.0	21.6
1044	63.0	21.8
1058	64.0	21.8
1078	65.0	21.8
1106	64.5	21.8
1117	64.5	21.8
1128	64.5	21.8

Mean Sample 2 result (last 5 readings): 64.5 mN/m            

Mean temperature (last 5 readings): 21.8 °C

pH of Sample 2: 6.2

 

 

Mean result: 65.8 mN/m

Temperature: 21.9 ± 0.5 ºC

Discussion:

The torsion balance was checked for accuracy using a 0.500 g certified weight. According to criteria mentioned in EC Method A.5, substances showing a surface tension lower than 60 mN/m under the conditions of this method should be regarded as being surface-active.

 

 

Conclusion:

The mean surface tension of duplicate saturated solutions of test item in water has been determined to be 65.8 mN/m at 21.9 ± 0.5 °C. The test item was considered to be not surface-active.

Conclusions:

The mean surface tension of duplicate saturated solutions of test item in water has been determined to be 65.8 mN/m at 21.9 ± 0.5 °C. The test item was considered to be not surface-active.

Executive summary:

EU Method A.5. – The surface tension of the test item was determined using the ring method.  The procedure employed was designed to be compatible with Method A.5. Surface Tension of Commission Regulation (EC) No 440/2008 of 30 May 2008.

An instrumentation calibration was performed using ultra-pure water. Duplicate 90 % saturated solutions of test item in ultra-pure water, were prepared, introduced to the appliance and thermally equilibrated to 21.9 °C ± 0.5 °C.  Two tests were carried out, the surface tension of each solution was measured repeatedly until the last five determinations were equal or differed by less than 0.5 mN/m.

The mean surface tension following measurement of duplicate 90 % saturated solutions of test item in ultra-pure water was determined to be 65.8 mN/m at 21.9 °C.

Description of key information

Surface Tension:  65.8 mN/m at 21.9 ± 0.5 °C; EU Method A.5.; R. Butler (2018)

Key value for chemical safety assessment

Surface tension:

65.8

Additional information

EU Method A.5. – The surface tension of the test item was determined using the ring method.  The procedure employed was designed to be compatible with Method A.5. Surface Tension of Commission Regulation (EC) No 440/2008 of 30 May 2008.

An instrumentation calibration was performed using ultra-pure water. Duplicate 90 % saturated solutions of test item in ultra-pure water, were prepared, introduced to the appliance and thermally equilibrated to 21.9 °C ± 0.5 °C.  Two tests were carried out, the surface tension of each solution was measured repeatedly until the last five determinations were equal or differed by less than 0.5 mN/m.

The mean surface tension following measurement of duplicate 90 % saturated solutions of test item in ultra-pure water was determined to be 65.8 mN/m at 21.9 °C.