Dodecylbenzenesulphonic acid, compound with isopropylamine (1:1)

Melting point / freezing point

Administrative data

Endpoint:

melting point/freezing point

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2018

Report date:

2018

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 102 (Melting point / Melting Range)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method A.1 (Melting / Freezing Temperature)

Deviations:

no

Test guideline 3

Qualifier:

according to guideline

Guideline:

EPA OPPTS 830.7200 (Melting Point / Melting Range)

Deviations:

no

GLP compliance:

yes

Type of method:

differential scanning calorimetry

Test material

Test material information

Constituent 1

Reference substance name:

Dodecylbenzenesulphonic acid, compound with isopropylamine (1:1)

EC Number:

247-556-2

EC Name:

Dodecylbenzenesulphonic acid, compound with isopropylamine (1:1)

Cas Number:

26264-05-1

Molecular formula:

C18H30O3S.C3H9N

IUPAC Name:

sodium dodecylbenzenesulfonate

Test material form:

liquid

Results and discussion

Melting / freezing point

Atm. press.:

ca. 101.3 kPa

Decomposition:

yes

Decomp. temp.:

> 275 °C

Sublimation:

no

Remarks on result:

not determinable

Any other information on results incl. tables

Preliminary test: Starting at 350°C, the weight of the sample decreased significantly. At 375°C, the sample weight had decreased by 25%. After the experiment, black residue was observed on the lid of the sample container and a black residue remained in the sample container (original colour: amber). The change of the colour indicated reaction and/or decomposition of the test item.

Main test:

During cooling, a small exothermic peak was observed between -20°C and 0°C. The exothermic effect was most likely obtained due to crystallization of a part of the test item. A glass transition was observed between -90°C and -60°C. During heating, two glass transitions were observed between -75°C and -25°C. The inflection point temperature of the first glass transition was -63.768°C. The inflection point temperature of the second glass transition was -0.560°C. An endothermic peak was observed between 25°C and 200°C. The endothermic effect was due to evaporation of volatile components (the test item contains 2.3% water). Endothermic peaks were observed starting at 275°C. The endothermic effects were due to reaction and/or decomposition of the test item. After the experiment, a black residue remained in the sample container.

Experiment 2 was performed to determine duplicate glass transition temperatures. The inflection point temperature of the first glass transition was -63.271°C. The inflection point temperature of the second glass transition was -1.205°C.  After the experiment, the sample appeared to have been unchanged, i.e. no decomposition and/or evaporation were observed. The glass transition temperatures were determined as the mean glass transition temperature of Experiment 1 (-63.768°C) and Experiment 2 (-63.271°C) for the first glass transition and Experiment 1 (-0.560°C) and Experiment 2 (-1.205°C) for the second glass transition.

Applicant's summary and conclusion

Conclusions:

No melting point was observed for the substance. Two glass transitions of the test substance were observed alongside decomposition at temperatures greater than 275°C.