Benzyltrimethylammonium hydroxide

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 March 2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

The substance can be produced through different process routes, yielding solutions in water or organic solvent (e.g. methanol or ethylene glycol).
It was initially unclear how to register the substance (mono-constituent or multi-constituent substance) and which manufactured substance to test to fulfil the REACH data requirements. After consultation with the ECHA helpdesk, the test program was started with the manufactured substance of the Lead registrant (solvent: methanol) in which the highest amount of solvent could be removed without causing degradation of the substance. This resulted in the selection of a solution of 56-57% BTMAOH in methanol as test substance.
During the course of the test program, and in order to aid meaningful risk assessment, after consultation with ECHA and upon ECHA's recommendation, it was considered to be more appropriate to test the water-based manufactured substance. As a consequence, some testing was performed with a BTMAOH solution in methanol, and some testing was performed with a BTMAOH solution in water.

The current entry reflects a test performed with a water-based test solution.

Qualifier:

according to guideline

Guideline:

EU Method A.5 (Surface Tension)

Version / remarks:

2016

Deviations:

no

Qualifier:

according to guideline

Guideline:

OECD Guideline 115 (Surface Tension of Aqueous Solutions)

Version / remarks:

1995

Deviations:

no

GLP compliance:

yes

Type of method:

OECD harmonised ring method

Key result

Surface tension:

74.7 mN/m

Temp.:

20 °C

Remarks on result:

other: Conc.= 1 g/L (corrected for the water content)

Key result

Surface tension:

75.3 mN/m

Temp.:

20 °C

Conc.:

1 g/L

Table 1: Surface tension measurements at 1 g/L (corrected for the water content)

Measurement	Time passed after transfer test solution to test vessel [minutes]	Surface tension (mN/m)
		individual	mean (1)	mean (2)
1	15	73.4	74.0^1	74.7
2	16	73.8
3	17	73.9
4	18	74.3
5	19	74.2
6	20	74.0

(1) Mean calculated from measurements 2 to 6, after equilibrium was reached.

(2) Mean multiplied by the calibration factor and Harkins-Jordan corrected.

Table 2: Surface tension measurements at 1 g/L

Measurement	Time passed after transfer test solution to test vessel [minutes]	Surface tension (mN/m)
		individual	mean	mean (1)
1	15	74.5
2	16	74.3	74.6	75.3
3	17	74.8
4	18	74.8
5	19	74.8

(1) Mean multiplied by the calibration factor and Harkins-Jordan corrected.

Conclusions:

The surface tension of a solution of 1 g/L of Benzyltrimethylammonium hydroxide in water was determined to be 74.7 mN/m (at 20°C).
The surface tension of a solution of 0.2 g/L of Benzyltrimethylammonium hydroxide in water was determined to be 75.3 mN/m (at 20°C).

Executive summary:

The OECD harmonized ring method (EC A.5 and OECD 115) was performed (GLP-compliant study). Two test solutions were prepared from aqueous test material containing Benzyltrimethylammonium hydroxide: 1 g/L and 0.2 g/L.

The surface tension of solution of 1 g/L of Benzyltrimethylammonium hydroxide in water was determined to be 74.7 mN/m (at 20°C).

The surface tension of solution of 0.2 g/L of Benzyltrimethylammonium hydroxide in water was determined to be 75.3 mN/m (at 20°C).

According to the EC A.5 guideline Benzyltrimethylammonium hydroxide is not surface active.

Description of key information

The registered substance BTMAOH is not surface active.

Key value for chemical safety assessment

Surface tension:

74.7

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

1 000

Additional information

The surface tension of a solution of 1 g/L of the registered substance BTMAOH in water was determined to be 74.7 mN/m (at 20°C).