Potassium isobutyrate

Surface tension

Administrative data

Endpoint:

surface tension

Type of information:

experimental study

Adequacy of study:

key study

Study period:

7 February 2019

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2019

Report date:

2019

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 115 (Surface Tension of Aqueous Solutions)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

OECD harmonised ring method

Test material

Test material information

Constituent 1

Reference substance name:

Potassium isobutyrate

EC Number:

243-077-8

EC Name:

Potassium isobutyrate

Cas Number:

19455-20-0

Molecular formula:

C4H8O2.K

IUPAC Name:

potassium 2-methylpropanoate

Test material form:

solid: particulate/powder

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: sponsor/181101001
- Expiration date of the lot/batch: 31 October 2020
- Purity test date: 01 Nov 2018


STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: Room Temperature (20 ± 5 °C); Keep away from humidity
- Stability under test conditions: stable
- Solubility and stability of the test substance in the solvent/vehicle:

Stability in solvents: H2O: 96h; EtOH: unknown; acetone: unknown; CH3CN: unknown; DMSO: unknown
Solubility in solvents: H2O: > 1 g/L; EtOH: unknown; acetone: unknown; CH3CN: unknown; DMSO: unknown

Results and discussion

Surface tension

Key result

Surface tension:

>= 72.18 - <= 72.94 N/m

Temp.:

19.8 °C

Conc.:

1 g/L

Any other information on results incl. tables

The test item solution was held at constant temperature (20.0 ± 0.1 °C). 60 minutes after conclusion of the first measurement series, a second measurement series was performed for verification purposes.

The following values were recorded:

 Measured Values Test Item First Series

Measurement	Time	Mass	Surface Tension	Temperature
No	s	g	mN/m	°C
1	4.2	0.2990	72.94	19.9
2	5.1	0.2985	72.82	19.9
3	6.2	0.2973	72.53	19.9
4	7.1	0.2970	72.45	19.9
5	8.2	0.2980	72.70	19.9
6	9.1	0.2976	72.60	19.9
7	10.2	0.2973	72.53	19.9
8	11.1	0.2972	72.50	19.9
9	12.2	0.2975	72.57	19.9
10	13.1	0.2970	72.45	19.9
Mean			72.61
Standard Deviation			0.16

 

 Measured Values Test Item Second Series

Measurement	Time	Mass	Surface Tension	Temperature
No	s	g	mN/m	°C
1	4.2	0.2972	72.50	20.0
2	5.2	0.2963	72.28	20.0
3	6.2	0.2971	72.48	20.0
4	7.2	0.2959	72.18	20.0
5	8.1	0.2973	72.53	20.0
6	9.2	0.2971	72.48	20.0
7	10.2	0.2974	72.55	20.0
8	11.2	0.2966	72.35	20.0
9	12.2	0.2964	72.31	20.0
10	13.2	0.2973	72.53	20.0
Mean			72.42
Standard Deviation			0.13

After the first and the second measurement series, the difference between mean values was less than 5%. Therefore no additional measurement series was required.

Applicant's summary and conclusion

Conclusions:

The values of the single determinations show no significant difference (0.26% between mean values of the two measurement series). All measured values lay clearly above the threshold for surface tension which is stated in the guidelines.
The surface tension of the negative control was determined with a difference of 0.31 % from the stated literature value.
Therefore, the result of the test is considered valid and the test item Potassium isobutyrate is classified as “not surface active” in a concentration of 1.00 g/L.