N-[3-(dimethylamino)propyl]stearamide monoacetate

Surface tension

Link to relevant study record(s)

Reference

Endpoint:

surface tension

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2014-09-14 to 2014-10-29

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

comparable to guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 115 (Surface Tension of Aqueous Solutions)

Principles of method if other than guideline:

This study was conducted under EPA TSCA Good Laboratory Practice Standards (40 CFR 792)

GLP compliance:

no

Type of method:

plate method

Remarks:

The Wilhelmy Plate method was used.

Key result

Surface tension:

0.004 mN/m

Temp.:

23 °C

Conc.:

90 other: % solubility limit of the substance

Calculation of the Surface Tension at 90% of the Critical Micelle Concentration:

Based on OECD Guideline 115, Surface Tension of Aqueous Solutions, the surface tension of a test substance is determined at 90% of the solubility limit of the substance in water when this concentration is less than 1 g/L.

Surface tension data employed for the assessment of water solubility for the test substance are presented in the study. This data is utilized to calculate the surface tension of the test substance at 90% of the solubility limit (as wt% total active substance) in water.

The surface tension of the test substance was calculated at 90% of the water solubility of the total active substance employing the linear least squares regression line for the linear region for total active substance concentrations less than 0.0100 wt% total active substance/L (data points
1 - 7).

Data Points 1 – 7

Slope (m1) = -11.03

Intercept (b1) = 17.37

r2 = 0.86

 

Employing the equation for linear least squares regression line and solving for y (surface tension in dyn/cm):

y₁ =m₁x+b₁

where,

x = log(solubility as wt% total active substance x 0.9) = log(0.0129 x 0.90)
= -1.94

y = surface tension = (-11.03 * x) + 17.37 = (-11.03 * -1.94) +17.37 = 38.8 dyn/cm

 

 

Conclusions:

Based on OECD Guideline 115, Surface Tension of Aqueous Solutions, the surface tension of a test substance was determined at 90% of the water solubility limit of the substance when this concentration is less than 1 g/L. The surface tension was 0.00388 mN/m

Executive summary:

The values for surface tension for the test substance were determined experimentally employing measurements of surface tension at multiple concentrations of the test substance in water. The experimental data were employed to determine the critical micelle concentration. The surface tension at 90% water solubility was 38.8 dyn/cm (0.00388 mN/m).

Description of key information

The values for surface tension was determined based on measurement of surface tension at multiple test substance concentrations in water to determine the Critical Micelle Concentration for the test substance. The surface tension at 90% water solubility (116.1 mg/L) was 38.8 dyn/cm (0.00388 mN/m).

Key value for chemical safety assessment

Surface tension:

0.004

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

116.1