4-[bis(phenylsubstituted)substituted]phthalic acid

Surface tension

Administrative data

Endpoint:

surface tension

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Experimental starting date: 13 December 2017. Experimental completion date: 08 March 2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2018

Report date:

2018

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 115 (Surface Tension of Aqueous Solutions)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method A.5 (Surface Tension)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

ring method

Test material

Reference

Name:

Unnamed

Type:

Constituent

Test material form:

solid: particulate/powder

Results and discussion

Surface tension

Surface tension:

67.5 mN/m

Temp.:

20 °C

Conc.:

1 g/L

Remarks on result:

other: Due to the instability of the test item in water, the result essentially represents that of the hydrolysis product

Any other information on results incl. tables

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

Sample 1

Age of Solution (min)	Reading (mN/m)	Temperature (°C)
134	69.5	19.8
146	69.5	19.8
180	69.5	19.8
194	69.5	19.8
206	69.5	19.8

Sample 2

Age of Solution (min)	Reading (mN/m)	Temperature (°C)
219	63.0	19.8
232	64.0	19.8
244	64.0	19.8
305	64.5	19.8
317	65.0	19.8
329	65.5	19.8
341	66.0	19.8
354	66.0	19.8
366	66.0	19.8
378	66.0	19.8

Mean Sample 1 result : 69.5 mN/m pH of Sample 1 : 2.6

Mean Sample 2 result : 65.9 mN/m pH of Sample 2 : 2.6

Overall result : 67.5 ± 2.0 mN/m

Overall temperature : 20.0 ± 0.5 ºC

Discussion:

The surface tension test had been performed before the water solubility test. At that point it wasn’t known how unstable in water the test item was. This was later confirmed after the water solubility preliminary test. Due to such instability, it was considered

that repeating the surface tension test was not required; this was because the test item would have degraded significantly in the time it took to do the test. Therefore, it was considered that the result from this test essentially represented that of the hydrolysis products.

The hydrolysis of the test item can also be seen in the pH of the samples. As the structure of the test item had no acidic functional groups, the solution pH inferred that acidic hydrolysis products were present.

According to criteria stated 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.

Applicant's summary and conclusion

Conclusions:

The surface tension at nominally 1 g/L of hydrolysed test item in water was determined to be 67.5 ± 2.0 mN/m at 20.0 ± 0.5 ºC. Due to the instability of the test item in water, the result essentially represented that of the hydrolysis products. The hydrolysed test item was considered not to be surface-active.

Executive summary:

The determination was carried out by a ring method, using a procedure designed to be compatible with Method A.5 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 at nominally 1 g/L of hydrolysed test item in water was determined to be  67.5 ± 2.0 mN/m at 20.0 ± 0.5 ºC. Due to the instability of the test item in water, the result  essentially represented that of the hydrolysis products. The hydrolysed test item was  considered not to be surface-active.