Tris(4-chlorophenyl)sulfonium 5-benzoyl-4-hydroxy- 2-methoxybenzenesulfonate

Melting point / freezing point

Administrative data

Endpoint:

melting point/freezing point

Type of information:

experimental study

Adequacy of study:

key study

Study period:

15 May - 14 Jun 2007

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP - Guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2007

Report date:

2007

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 102 (Melting point / Melting Range)

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method A.1 (Melting / Freezing Temperature)

GLP compliance:

yes (incl. QA statement)

Remarks:

Food and Consumer Product Safety Authority, Den Haag, The Netherlands

Type of method:

thermal analysis

Remarks:

differential scanning calorimetry

Test material

Reference

Name:

Unnamed

Type:

Constituent

Test material form:

solid: particulate/powder

Remarks:

migrated information: powder

Details on test material:

- Name of test material (as cited in study report): PM-5927
- Physical state:off-white powder
- Lot/batch No.:07-02
- Expiration date of the lot/batch:05.02.2008
- Storage condition of test material: at room temperature protected from light

Results and discussion

Melting / freezing point

Melting / freezing pt.:

144 °C

Atm. press.:

ca. 1 013 hPa

Decomposition:

yes

Remarks on result:

other: decomposition temperature not reported

Any other information on results incl. tables

The melting temperature is defined as the temperature at which the phase transition from solid to liquid state takes place at normal atmospheric pressure. This temperature ideally corresponds to the solidification or freezing temperature.

The melting temperature or boiling temperature (if any) of a pure substance is evaluated from a DSC-curve as the extrapolated onset temperature of the endothermic melting or evaporation peak, i.e. as the cross point of the extrapolated base line and the linear part of the rising section of the melting or evaporation peak.

Melting, boiling and/or other relevant decomposition temperatures are given in degrees Celsius (°C) and Kelvin (K). Temperature in Kelvin = Temperature in °C + 273.15.

Preliminary test

TGA-curve shows that was recorded during the preliminary test. From approximately 140 °C until 225 °C, a small weight change was observed which was probably caused by evaporation of a small fraction (approximately 2%) of the test substance. From approximately 225 °C upwards the weight of the sample decreased significantly. At 338 °C, the sample weight had decreased by 25%. After the experiment, a black coloured (original colour: off-white), swollen, brittle residue remained in the sample container. The change of the colour indicates reaction and/or decomposition of the test substance.

Main study

The DSC-curve shows that was recorded during the first experiment (25 °C – 338 °C). An endothermic peak was observed between 125 °C and 175 °C. This effect was probably caused by melting of the test substance. The extrapolated onset temperature of this peak was 144 °C. Several endothermic and exothermic effects were observed at temperatures > 215 °C, which were probably due to reaction and/or decomposition of the test substance. After the experiment, a dark red coloured molten residue remained in the sample container (original colour: off-white). The change of colour indicated that the test substance had reacted and/or decomposed.

DSC-curves that were recorded during the second experiment (25 °C – 200 °C; cooling not reported in detail). The extrapolated onset temperature of the endothermic peak obtained with the first heating was 143 °C. During the second heating, the endothermic peak was shifted significantly to lower temperatures. After the experiment, a yellow molten residue remained in the sample container (original colour: off-white). The change of colour and the shift of the endothermic peak indicated that the test substance possibly had reacted and/or decomposed during melting.

The DSC-curves that were recorded during the third experiment (25 °C – 165 °C; cooling not reported in detail). Essentially the same results as during the second experiment were obtained. To demonstrate that the endothermic peak was due to melting of the test substance the fourth experiment (25 °C – 180 °C) was performed with a rate of 5 °C/minute. The endothermic peak was observed between 110 °C and 175°C. The extrapolated onset temperature of this peak was 142 °C. After the experiment, a yellow molten residue remained in the sample container (original colour: off-white). Since a similar temperature was observed at which the endothermic effect occurred it can be concluded that the observed effect was due to melting of the test substance.

The melting temperature of the test substance was determined using the extrapolated onset temperatures obtained with experiments 1 - 3 since all experiments were performed using a heating rate of 20 °C/minute. The mean melting temperature of the test substance is 144 °C.

Reaction and/or decomposition of the test substance was observed during melting. Boiling of test substance was not observed below the temperature at which reaction and/or decomposition started Therefore, the test substance has no boiling temperature.