Ethyltriphenylphosphonium iodide

Melting point / freezing point

Link to relevant study record(s)

Reference

Endpoint:

melting point/freezing point

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2017-03-14 to 2017-05-16

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 102 (Melting point / Melting Range)

Version / remarks:

adopted 27 July, 1995

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method A.1 (Melting / Freezing Temperature)

Version / remarks:

30 May, 2008

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

differential scanning calorimetry

Key result

Melting / freezing pt.:

170 °C

Atm. press.:

1 013 Pa

Decomposition:

yes

Remarks:

after melting

Sublimation:

no

Remarks on result:

other: decomposition temperature not measureable with DSC

Preliminary test:

Two steps were registered with maxima at 383 °C resp. 484°C. A total mass loss of 99.5 % at the final temperature could be observed (mass change in the range until 410°C: 86.4 %; mass change in the range from 410 to 600°C: 13.1 %). No significant mass loss occurred due to purging. The course of the thermogravimetric curve suggests decomposition of the test item.

After cooling the residue was brown-black inside the crucible.

Main test:

The DSC measurements were performed twice in the temperature range from 20 - 440°C resp. from 20 - 450°C. A sharp endothermic peak indicating a melting point could be observed (peak maximum: 173°C / 172 °C; extrapolated onset temperature: 170 °C / 169.87 °C; rounded mean of both determinations: 170°C). Upon further heating the DSC-curve showed one more wide endothermic peak (peak maximum: 388°C/ 388°C; extrapolated onset temperature: 359.60 °C / 359.88 °C) followed by an exothermic peak (peak maximum: 409°C / 409 °C). Due to the fact that the thermogravimetric measurement did not show a complete mass loss in that temperature range, no normal boiling point could be observed. The endothermic peak changed into an exothermic peak. This suggests a possible boiling of the main compound with simultaneous decomposition. Reweighing after the measurement showed that the sample had lost 71.6 % / 70.6 % of its mass. The residue looked brown-black on the bottom of the crucible.

Conclusions:

The melting temperature of Ethyltriphenylphosphonium iodide was determined to be 170°C.

Description of key information

170°C

Key value for chemical safety assessment

Melting / freezing point at 101 325 Pa:

170 °C

Additional information

GLP study according to OECD Guideline 102 (27 July 1995) and EU Method A.1 (30 May, 2008) using differential scanning calorimetry