Alkylbenzenesulphonic acid compound with alkanolamine

Additional physico-chemical information

Administrative data

Endpoint:

other: Critcal Micelle Concentration

Type of information:

experimental study

Adequacy of study:

key study

Study period:

24 December 2015 to 22 March 2016

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: study under GLP

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2016

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

other: ISO 4311: Anionic and non-ionic surface active agents — Determination of the critical micellization concentration — Method by measuring surface tension with a plate, stirrup or ring

GLP compliance:

yes

Test material

Reference

Name:

Unnamed

Type:

Constituent

Test material form:

semi-solid (amorphous): gel

Remarks:

paste

Details on test material:

Identification DDBSA/DIOPA
Appearance Off-white to light yellow paste

Results and discussion

Results:

CMC was determined from the plot of the surface tension of the test solutions as function of log C based on the interception of 2 trendlines from the test solutions with nominal test item concentrations of 10.3, 35.0 and 100.0 mg/L and from the test solutions with nominal test item concentrations of 1005.0, 3007.0 and 10006.7 mg/L (mean values).

The intersection was calculated to be log C = 2.71. It corresponded with a CMC of 510 mg/L.

Any other information on results incl. tables

Measurement at 20°C±0.5°C	Time passed [minutes]	Mean Surface Tension [mN/m]
1 mg/L	15-19	72.9 (Φb=1.02)
10 mg/L	15-19	72.4 (Φb=1.02)
35 mg/L	18-22	66.4 (Φb=1.00)
100 mg/L	15-19	49.4 (Φb=1.02)
1000 mg/L	15-19	36.7 (Φb=1.02)
3000 mg/L	17-21	35.3 (Φb=1.00)
10000 mg/L	16-20	34.5 (Φb=1.02)

Applicant's summary and conclusion

Conclusions:

The critical micelle concentration of the substance is 520 mg/L

Executive summary:

The CMC was determined by measuring the surface tension of test substance solutions at different concentrations. No further decrease of surface tension was measured at 520 mg/L (extrapolated value).