Poly[oxy(methyl-1,2-ethanediyl)], .alpha.-[2-[bis(phosphonomethyl)amino]methylethyl]-.omega.-[2-[bis(phosphonomethyl)amino]methylethoxy]-, sodium salt (1:?)

Surface tension

Link to relevant study record(s)

Reference

Endpoint:

surface tension

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Testing was conducted between 15 June 2011 and 20 December 2011.

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

Study conducted in compliance with agreed protocols, with no or minor deviations from standard test guidelines and/or minor methodological deficiencies, which do not affect the quality of the relevant results. The study report was conclusive, done to a valid guideline and the study was conducted under GLP conditions.

Qualifier:

equivalent or similar to guideline

Guideline:

EU Method A.5 (Surface Tension)

Version / remarks:

The surface tension was determined using a ring method based on ISO 304

Deviations:

yes

Remarks:

The surface tension result was not corrected using the Harkins-Jordan correction table as the correction is not applicable to the apparatus used.

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 115 (Surface Tension of Aqueous Solutions)

Version / remarks:

The surface tension was determined using a ring method based on ISO 304

Deviations:

yes

Remarks:

The surface tension result was not corrected using the Harkins-Jordan correction table as the correction is not applicable to the apparatus used.

Principles of method if other than guideline:

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.

GLP compliance:

yes (incl. QA statement)

Type of method:

ring method

Key result

Surface tension:

70.7 mN/m

Temp.:

21.5 °C

Conc.:

1 g/L

Remarks on result:

other: Concentration corrected for Water Content (g/L)

Key result

Surface tension:

70.5 mN/m

Temp.:

21.2 °C

Conc.:

0.976 g/L

Remarks on result:

other: Concentration corrected for Water Content (g/L)

Calibration factor

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

Determination 1

Reading (mN/m)	Temperature (ºC)	Literature Value (mN/m)	Calibration Factor
72.5	20.8	72.60	1.001
72.5	20.8	72.60	1.001
73.0	20.8	72.60	0.995
72.0	20.8	72.60	1.008
72.5	20.8	72.60	1.001
72.5	20.8	72.60	1.001
Mean Calibration Factor = 1.001

Determination 2

Reading (mN/m)	Temperature (ºC)	Literature Value (mN/m)	Calibration Factor
73.0	21.2	72.53	0.994
72.5	21.4	72.50	1.000
73.0	21.4	72.50	0.993
72.5	21.6	72.47	1.000
72.5	21.6	72.47	1.000
73.0	21.6	72.47	0.993
Mean Calibration Factor = 0.997

 

Sample solution readings

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

Determination 1

Time (mins)	Reading (mN/m)	Temperature (ºC)
77	70.0	20.8
87	70.5	20.8
96	70.5	20.8
107	70.5	20.8
117	70.5	20.8

Mean reading            :   70.4 mN/m
Surface tension            = reading x calibration factor
                                     = 70.4 x 1.001
                                     = 70.5 mN/m
Temperature                :   21.0 ± 0.5ºC
pH of sample solution  :    4.9
Concentration              :   1.020 g/l (0.976 g/l corrected for water content)

Determination 2

Time (mins)	Reading (mN/m)	Temperature (ºC)
152	71.0	21.4
162	71.0	21.4
170	71.0	21.4
178	70.5	21.4
190	71.0	21.4

Mean reading          :          70.9 mN/m
Surface tension      =         reading x calibration factor
            =         70.9 x 0.997
            =         70.7 mN/m
Temperature:           21.5 ± 0.5ºC
pH of sample solution:          5.0
Concentration         :          1.049 g/l (1.004 g/l corrected for water content) The test item is not considered to be surface-active.

Conclusions:

The surface tension of the test item has been determined as follows:

Concentration corrected for water content (g/l) Surface Tension (mN/m) Temperature (ºC)
0.976 70.5 21.0 ± 0.5ºC
1.00 70.7 21.5 ± 0.5ºC

The test item is not considered to be surface-active.

Executive summary:

The determination was carried out using a White Electrical Institute Co. Ltd. torsion balance for surface and interfacial tension measurements and a procedure based on the ISO 304 ringthod. With the exception of the following deviation, the experimental procedure used was designed to be compatible with that specified in Method A5 Surface Tension of Commission Regulation (EC) No 440/2008 of 30 May 2008 and Method 115 of the OECD Guidelines for the Testing of Chemicals, 27 July 1995.

§    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.

The surface tension of the test item has been determined as follows:

Concentration (g/l)	Concentration corrected for Water Content (g/l)	Surface Tension (mN/m)	Temperature (ºC)
1.02	0.976	70.5	21.0± 0.5ºC
1.05	1.00	70.7	21.5± 0.5ºC

The test item is not considered to be surface-active.

Description of key information

In a single key study conducted in accordance with EU Method A.5., the surface tension was determined to be 70.7 mN/m at 21.0 ± 0.5°C. The substance is not considered to be surface active.

Key value for chemical safety assessment

Surface tension:

70.7

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

1 000

Additional information

The surface tension was determined using a ring method based on ISO 304, designed to be compatible with Method A5 Surface Tension of Commission Regulation (EC) No 440/2008 of 30 May 2008 and Method 115 of the OECD Guidelines for Testing of Chemicals, 27 July 1995. The results are as follows:

Concentration (g/l)	Concentration corrected for water content (g/l)	Surface Tension (mN/m)	Temperature (°C)
1.02	0.976	70.5	21.0 ± 0.5°C
1.05	1.00	70.7	21.5 ± 0.5°C

The test item was not considered to be surface-active.