3-(D-gluconoylamino)propyl(2-hydroxyethyl)dimethylammonium chloride

Melting point / freezing point

Link to relevant study record(s)

Reference

Endpoint:

melting point/freezing point

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

EU Method A.1 (Melting / Freezing Temperature)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

differential scanning calorimetry

Specific details on test material used for the study:

Test item 207516/A
Identification Quaternium-22
Appearance Brown paste (determined by Charles River Den Bosch)
Batch 0001954895
Purity/Composition > 90%
Test item storage In refrigerator (2-8°C)
Stable under storage conditions until 16 June 2017 (retest date)

Key result

Melting / freezing pt.:

-21.8 °C

Atm. press.:

1 atm

Decomposition:

no

Sublimation:

no

Remarks on result:

other: This value for melting point here is defined as glass-transition temperature (Tg), which is always lower than the actual melting temperature, Tm, if one exists.

During cooling an endothermic effect/glass transition (Tg) of the test item was observed between ‑10°C and ‑50°C (results are archived in the raw data). With heating a glass transition (Tg) of the test item was observed between -50°C and 0°C. The extrapolated inflection temperature was -21.662°C. Starting at 100°C, an endothermic effect was observed. The effect was due to the reaction and/or decomposition of the test item. After the experiment, a dark brown molten residue remained in the sample container. Black residue was observed on the lid of the sample container.

Experiment 2 was performed as a duplicate of Experiment 1. The temperature program was similar as the program of Experiment 1. The result was similar to what was found in Experiment 1. The extrapolated inflection temperature was -21.856°C.After the experiment it was observed that the test item was unchanged. The glass transition (TG) was determined as the average melting temperature obtained from experiment 1 (-21.662°C) and experiment 2 (-21.856°C).

Description of key information

The key value is based on a GLP study performed according to an EC directive. The extrapolated inflection temperature was -21.856°C.After the experiment it was observed that the test item was unchanged. The average melting temperature was obtained from the glass transition temperature(Tg) determined in experiment 1 (-21.662°C) and experiment 2 (-21.856°C). The liquid-glass transition is the reversible transition in amorphous materials  from a viscous or rubbery state to a hard and relatively brittle "glassy" state as the temperature is decreased. In experiments where 1-Propanaminium, 3-(D-gluconoylamino)-N-(2-hydroxyethyl)-N,N-dimethyl-, chloride of >90% purity was tested, it was defined as a thick paste at room temperature. Based on the smiles notation, QSAR program MPBPWIN (v1.43) predicted a melting point of >300°C (Tm). However, in the experiment the substance lost mass and changed colour above 125°C indicating possible decomposition. Therefore it was decided to base the key value for the melting/freezing point on the Tg.

Key value for chemical safety assessment

Melting / freezing point at 101 325 Pa:

-21.8 °C