Reaction product of 3,5,5-trimethyl-hexanoic acid and 2-methylpropanoic acid and pentaerythritol

Surface tension

Link to relevant study record(s)

Reference

Endpoint:

surface tension

Type of information:

experimental study

Adequacy of study:

key study

Study period:

15 July 2011 - 09 February 2012

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

Study was conducted in accodance with International guidelines and GLP. All guideline validity criteria were met.

Qualifier:

according to guideline

Guideline:

OECD Guideline 115 (Surface Tension of Aqueous Solutions)

Version / remarks:

27 July 1995

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method A.5 (Surface Tension)

Version / remarks:

Commission Regulation (EC) No 440/2008 laying down test methods pursuant to Regulation (EC) No 1907/2006 of the European Parliament and of the Council on the Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH).

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

OECD harmonised ring method

Specific details on test material used for the study:

RADIOLABELLING INFORMATION (if applicable)
- Radiochemical purity: N/A
- Specific activity: N/A
- Locations of the label: N/A
- Expiration date of radiochemical substance: N/A

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: Room temperature in the dark and under nitrogen.
- Stability under test conditions: Assumed stable.
- Solubility and stability of the test substance in the solvent/vehicle: 90 % saturated aqueous solution prepared for testing.
- Reactivity of the test substance with the solvent/vehicle of the cell culture medium: N/A

TREATMENT OF TEST MATERIAL PRIOR TO TESTING
- Treatment of test material prior to testing: N/A
- Preliminary purification step (if any): N/A
- Final dilution of a dissolved solid, stock liquid or gel: N/A
- Final preparation of a solid: N/A

FORM AS APPLIED IN THE TEST (if different from that of starting material): Applied as supplied.

TYPE OF BIOCIDE/PESTICIDE FORMULATION (if applicable): N/A

OTHER SPECIFICS: No

Key result

Surface tension:

54.5 mN/m

Temp.:

20 °C

Conc.:

90 other: % saturation

Table 1       Surface tension results

Time (mins)	Surface tension (mN/m)
	Measured		Calibration corrected
	A	B	A	B
0	57.5	56.0	57.7	56.2
5	58.0	54.0	-	-
10	58.5	55.5	-	-
15	58.5	56.0	-	-
20	58.5	56.0	-	-
25	59.0	56.5	-	-
30	59.0	57.0	-	-

 

Mean calibration corrected surface tension = 57.0 mN/m. Only the initial reading was considered as the slow increasing trend in results was consistent with gradual evaporation of dissolved components from solution.

 

Harkins-Jordan corrected value = 54.5 mN/m

Conclusions:

The surface tension of a 90 % saturated aqueous solution of Tetraesters of pentaerythritol with 2- methylpropanoic acid and 3,5,5-trimethyl-hexanoic acid was found to be 54.5 mN/m.

Executive summary:

OECD 115 (2012) - The surface tension of a 90 % saturated aqueous solution was determined with a surface tension torsion balance using the OECD harmonised ring method.

 

Test substance (approximately 0.5 g) was combined with purified water (500 ml) and mixed at 20 °C for 3 days. After this period, a portion was centrifuged (2500 rpm, 10 minutes, 20 °C) and an aliquot (45 ml) of the clear aqueous phase then diluted to 50 ml with purified water to produce a 90 % saturated aqueous solution for measurement. A second sample was similarly prepared.

 

The test vessel was half filled with liquid, put on the tensiometer test platform, and raised so that the ring was just below the liquid surface. The platform was lowered to draw a lamella from the liquid surface. The maximum force which arose just before the lamella was torn off is the surface tension and was recorded. Measurements were made at intervals until a constant value (to within 0.5 mN/m) was recorded.

 

The mean calibration corrected surface tension was 57.0 mN/m. Only the initial reading was considered as the slow increasing trend in results was consistent with gradual evaporation of dissolved components from solution. The Harkins-Jordan* corrected value was determined to be 54.5 mN/m.

 

The surface tension of a 90 % saturated aqueous solution of Tetraesters of pentaerythritol with 2- methylpropanoic acid and 3,5,5-trimethyl-hexanoic acid was found to be 54.5 mN/m at 20 ºC.

 

*HARKINS, W.D. and JORDAN, H.F., J. Amer. Chem. Soc. 52, 1751 (1930).

Description of key information

Surface tension = 54.5 mN/m at 20 ºC in a 90 % saturated aqueous solution; OECD 115; Sydney, P. (2012)

Key value for chemical safety assessment

Surface tension:

54.5

Additional information

OECD 115 (2012) - The surface tension of a 90 % saturated aqueous solution was determined with a surface tension torsion balance using the OECD harmonised ring method.

 

Test substance (approximately 0.5 g) was combined with purified water (500 ml) and mixed at 20 °C for 3 days. After this period, a portion was centrifuged (2500 rpm, 10 minutes, 20 °C) and an aliquot (45 ml) of the clear aqueous phase then diluted to 50 ml with purified water to produce a 90 % saturated aqueous solution for measurement. A second sample was similarly prepared.

 

The test vessel was half filled with liquid, put on the tensiometer test platform, and raised so that the ring was just below the liquid surface. The platform was lowered to draw a lamella from the liquid surface. The maximum force which arose just before the lamella was torn off is the surface tension and was recorded. Measurements were made at intervals until a constant value (to within 0.5 mN/m) was recorded.

 

The mean calibration corrected surface tension was 57.0 mN/m. Only the initial reading was considered as the slow increasing trend in results was consistent with gradual evaporation of dissolved components from solution. TheHarkins-Jordan* corrected value was determined to be 54.5 mN/m.

 

The surface tension of a 90 % saturated aqueous solution of Tetraesters of pentaerythritol with 2- methylpropanoic acid and 3,5,5-trimethyl-hexanoic acid was found to be 54.5 mN/m at 20 ºC.

To be surface active, a molecule must be partially hydrophillic and partially hydrophobic. Though the substance does contain molecules with hydrophillic (carbonyl oxygens with lone pairs) and hydrophobic (extended carbon chains) portions, it is the topology of the molecules within the substance which hinders its ability to act as a "classic surfactant". Due to the tetrahedral shape of the molecules within the substance, there is no confirmation in which section of the molecules could interact with water i.e. each of the "limbs" of the molecules prevent the lone pairs on the carbonyl oxygen from interacting with the water, as a surface active molecule should. Taking this discussion into account, we can conclude that the substance would exhibit only slight surface active characteristics and to this end, the HPLC methods used to derive the Log KOW and Log KOC would produce reliable endpoints.

 

*HARKINS, W.D. and JORDAN, H.F., J. Amer. Chem. Soc. 52, 1751 (1930).