Fatty acids, C16-18 (even numbered), ammonium salts

Melting point / freezing point

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

melting point/freezing point

Type of information:

(Q)SAR

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

results derived from a valid (Q)SAR model and falling into its applicability domain, with adequate and reliable documentation / justification

Remarks:

Internationally accepted method, EPI-Suite, EPA (USA)

Justification for type of information:

See attached the QMRF and QPRF for the QSAR model

Guideline:

other: REACH Guidance on QSARs R.6

Principles of method if other than guideline:

Gold, P.I. and Ogle, G.J. 1969. Estimating thermophysical properties of liquids. Part 4 - Boiling, freezing and triple-point temperatures. Chem. Eng. 76: 119.
Joback, K.G. 1982. A Unified Approach to Physical Property Estimation Using Multivariate Statistical Techniques. Stevens Institute of Technology, submitted to the Dept. of Chem. Eng. for M.S. Degree at the Massachusetts Institute of Technology in June 1984.
Reid, R.C., Prausnitz, J.M. and Poling, B.E. 1987. The Properties of Gases and Liquids. Fourth edition. NY: McGraw-Hill, Inc., Chapter 2.

Specific details on test material used for the study:

SMILES: N(H)(H)(H)(H)OC(=O)CCCCCCCCCCCCCCCCC

Key result

Melting / freezing pt.:

213.23 °C

Atm. press.:

1 atm

Remarks on result:

other: QSAR predicted value

MPBPVP predicted that ammonium stearate has a melting point of 213.23ºC.

Conclusions:

The estimated melting point is 213.23 ºC (EPI-Suite, MPBPWIN v1.43)

Executive summary:

The substance estimated melting point is 213.23 ºC (EPI-Suite, MPBPWIN v1.43)

Reference 2

Endpoint:

melting point/freezing point

Type of information:

(Q)SAR

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

results derived from a valid (Q)SAR model and falling into its applicability domain, with adequate and reliable documentation / justification

Remarks:

Internationally accepted method, EPI-Suite, EPA (USA)

Justification for type of information:

See attached the QMRF and QPRF for the QSAR model

Guideline:

other: REACH Guidance on QSARs R.6

Principles of method if other than guideline:

Gold, P.I. and Ogle, G.J. 1969. Estimating thermophysical properties of liquids. Part 4 - Boiling, freezing and triple-point temperatures. Chem. Eng. 76: 119.
Joback, K.G. 1982. A Unified Approach to Physical Property Estimation Using Multivariate Statistical Techniques. Stevens Institute of Technology, submitted to the Dept. of Chem. Eng. for M.S. Degree at the Massachusetts Institute of Technology in June 1984.
Reid, R.C., Prausnitz, J.M. and Poling, B.E. 1987. The Properties of Gases and Liquids. Fourth edition. NY: McGraw-Hill, Inc., Chapter 2.

Specific details on test material used for the study:

SMILES: N(H)(H)(H)(H)OC(=O)CCCCCCCCCCCCCCC

Key result

Melting / freezing pt.:

202.39 °C

Atm. press.:

1 atm

Remarks on result:

other: QSAR predicted value

MPBPVP predicted that ammonium palmitate has a melting point of 202.39ºC

Conclusions:

The estimated melting point is 202.39 ºC (EPI-Suite, MPBPWIN v1.43)

Executive summary:

The substance estimated melting point is 202.39 ºC (EPI-Suite, MPBPWIN v1.43)

Reference 3

Endpoint:

melting point/freezing point

Data waiving:

study technically not feasible

Justification for data waiving:

other:

Justification for type of information:

JUSTIFICATION FOR DATA WAIVING
The study is technically not feasible since the substance decomposes before melting.

Reference 4

Endpoint:

melting point/freezing point

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

12.12.2012

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Remarks:

Test method according to internal procedures. Scientifically reliable.

Principles of method if other than guideline:

- Principle of test: The melting point of the substance Fatty acids, C16 -18 (even numbered), ammonium salts in water solution was investigated by DSC (differential scanning calorimetry) method.

GLP compliance:

no

Key result

Melting / freezing pt.:

> 70 - < 120 °C

Decomposition:

yes

Remarks:

(ammonium and fatty acids)

In the first heating rate the endothermic effects could be observed in the temperature range of 70ºC to 120 ºC, which could be allocated to the melting of the test item. In the literature a melting range of 90 to 110 °C is mentioned. But under air, ammonia is lost. At higher temperature ammonia is also lost (endothermic area between 120 °C and 180 °C).

In the second heating rate the endothermic effect between 70 to 180 °C was disappeared. There was a narrow endothermic peak between 40 and 70 °C. The calculated melting point was 54,55 °C.

As comparison the melting point of “Fatty acids, C16-18” was determined. The endothermic peaks were comparable.

Melting point of “Fatty acids, C16-18”: 56,95 °C.

Melting point of test item: 54,55 °C.

The differences were based on the slightly differential C-chain distributions.

Conclusions:

The study is not technically feasible since the test item is not stable and decomposes before melting. Ammonia is lost by higher temperatures or under air. A clear melting point was not detectable (melting range between 70 °C and 120 °C).

Description of key information

Data waiving (study technically not feasible): The study is technically not feasible since the substance decomposes before melting.

Additional information

Data waiving (study technically not feasible): The study is technically not feasible since the substance decomposes before melting.