Fatty acids, C16-18 and C18-unsatd., reaction products with triethanolamine, di-Me sulfate-quaternized

Explosiveness

Link to relevant study record(s)

Reference

Endpoint:

explosiveness, other

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: expert judgement

Principles of method if other than guideline:

Descripton of methods
-The assessment of reactive groups in the molecule was performed according to the data and principles described comprehensively in the literature (Bretherick, 1990)
-Calculations of thermodynamic properties were estimated using Benson's method of group additivity. For this purpose, the computer programme CHETAH (7.3) was utilised (ASTM 2001: CHETAH, rev. 7.3, Chemical Thermodynamic and Energy Release Evaluation. ASTM Subcommittee E27.07 on Estimation Methods, ASTM DS51C, West Conshohocken, PA, USA).
To this, it must be noted that partially unsaturated TEA-Esterquat is a quaternary ammonium compound, which as an entity can not be subject to such thermodynamic calculations. Instead, the calculations were done separately for the 'components' dimethylsulfuric acid and the respective triethanolamine (mono-, di- and tri-) esters. Furthermore, the current version of the CHETAH model (vers. 7.3) does not provide thermodynamic data for the following structural group (O-(C, SO2)), which is why the estimation for dimethylsulfuric acid was based on an interpolation between two related structures (O-(O, SO2) and O-(C, O)).

GLP compliance:

no

Parameter:

other: heat of decomposition

Remarks on result:

negative (not further specified)

Remarks:

for details see "Any other information on results"

Structural aspects: Initially, it can be stated that partially unsaturated TEA-Esterquat does not contain any typically reactive structural groups that would indicate a tendency of violent decomposition. Partially unsaturated TEA-Esterquat is a mixture of mono-, di- and triesters with chain lengths of C16, C18 and C18 (unsaturated). In this context, it is explicity noted that the components of partially unsaturated TEA-Esterquat contain an identical subset of structural increments (Benson groups), which is why in this statement, no further differentiation is made between the different ester chains and the C18 -chain length is used as the chemical lead. The unsaturated chain is an exemption, with the Benson groups (CH2 -(C, =C) and =C-(2C)) which however can be considered not to be reactive structural groups.

Maximum heat of decomposition

partially unsaturated TEA-Esterquat*: -411 cal/g (interploated value)

Dimethylsulfuric acid**: -786 cal/g (interploated value)

Monoester: -363 cal/g

Diester: -352 cal/g

Triester: -309 cal/g

*calculation performed for the product partially unsaturated TEA-Esterquat as a mixture of the key identified individual components

**calculation performed for each key identified individual components of the product partially unsaturated TEA-EQ

This is a measure of the energy to be released from the material itself, and has been shown to be highly correlated with the tendency of a material to deflagrate or detonate. A high rating is assigned by CHETAH if the calculated maximum enthalpy of decomposition is more exothermic than 700 cal/g (2929 J/g).

Difference between heat of combustion and heat of decomposition

partially unsaturated TEA-Esterquat*: -7181 cal/g (interploated value)

Dimethylsulfuric acid**: -1681 cal/g (interploated value)

Monoester: -7841 cal/g

Diester: -8406 cal/g

Triester: -8654 cal/g

The heat of combustion for partially unsaturated TEA-Esterquat was calculated as -7592 cal/g (interploated value)*. Since the heat of decomposition is much lower, this can be seen as an indication of a low tendency to be plosive.

Oxygen Balance

partially unsaturated TEA-Esterquat*: -243%

Dimethylsulfuric acid**: -63%

Monoester: -264%

Diester: -283%

Triester: -291%

A compound with exactly the amount of oxygen required for total combustion has an oxygen balance of 100%. Thus a compound with a negative oxygen balance is oxygen deficient. Experience has shown that this value is primarily of relevance for compounds consisting of C, H, N, and O.

Interpretation of results:

GHS criteria not met

Conclusions:

Structural aspects and estimated thermodynamic properties indicate that partially unsaturated TEA-Esterquat must not be considered to have explosive properties.

Executive summary:

Partially unsaturated TEA-Esterquat does not contain any structural groups known to be correlated with a particular explosion hazard. In addition, the thermodynamic calculations indicate that the heat of decomposition and the comparison with the heat of combustion does not necessitate explosivity to be expected. Finally, the overall oxygen balance is negative. In conclusion, structural aspects and estimated thermodynamic properties indicate that partially unsaturated TEA-Esterquat must not be considered to have explosive properties.

Description of key information

non explosive

Key value for chemical safety assessment

Explosiveness:

non explosive

Additional information

According to column 2 of REACH Annex VII, testing of explosive properties does not need to be conducted. The substance does not contain any structural groups known to be correlated with a particular explosion hazard. In addition, the thermodynamic calculations for the substance indicate that the heat of decomposition and the comparison with the heat of combustion does not necessitate explosivity to be expected. Finally, the overall oxygen balance is negative. In conclusion, the substance is not considered to have explosive properties.