Zinc methacrylate

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:

From 12 to 23 April 2012

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Reason / purpose for cross-reference:

reference to same study

Qualifier:

according to guideline

Guideline:

OECD Guideline 102 (Melting point / Melting Range)

Deviations:

not specified

Qualifier:

according to guideline

Guideline:

EU Method A.1 (Melting / Freezing Temperature)

Deviations:

not specified

Qualifier:

according to guideline

Guideline:

EPA OPPTS 830.7200 (Melting Point / Melting Range)

Deviations:

not specified

Qualifier:

according to guideline

Guideline:

other: SOP-LO-113 Thermal Stabilitiy via DSC

Deviations:

not specified

GLP compliance:

yes (incl. QA statement)

Type of method:

thermal analysis

Remarks:

and method Capillary method has been used

Key result

Decomposition:

yes

Remarks:

The test item decomposes firstly at a temperature of > 200 °C.

Decomp. temp.:

> 200 °C

Results:

The test item zincmethacrylateshowed an exothermal effect in the temperature range 220 – 310 °C with a decomposition energy of ‑250 J/g. In the temperature range of 390 – 430 °C an endothermic effect could be observed.

Table1: Results of the DSC-measurements on thermal stability

No.	Sample weight / mg	Start of effect / °C	Energy / J/g	Remaks
PN3640	10.15	220 390	-250 (exothermal) 80 (endothermic)	Figure 1

Melting and Boiling point:

The DSC runs PN3647, PN3651 and PN3653 are shown in figures 2, 3 and 4

In the temperature range of 5 – 70 °C an endothermic effect was detected. In the temperature range of approx. 120 – 190 °C an exothermal effect could be measured, with a decomposition energy of ‑30 J/g. Up to 200 °C no mass loss could be measured.

Table 2: Results of the first test series on melting and boiling point

No.	Sample weight / mg	Start of effect / °C	Energy / J/gR	Remarks
PN3647	10.12	5	20 (endothermic)	Figure 2
PN3651	9.86	--	--	Figure 3
PN3653	11.71	--	--	Figure 4

Measurements by the capillary method:

To verify the results of the DSC-measurement six additional measurements with the capillary method (Apparatus: Büchi melting Point B-540) was performed.

Table 3:Observations during the capillary method (Heating rate: 10 K/min from 26 °C to 410 °C)

	Sample 1-3	Sample 4-6
Filling height (each)	6 mm	5 mm
Start (26 °C)	white solid	white solid
197 °C	slight change of the colour from white to light brown, still solid	slight change of the colour from white to light brown, still solid
230 °C	change of the colour to brown, still solid (see figure 5)	change of the colour to brown, still solid
350 °C	change of the colour to dark brown, still solid	change of the colour to dark brown, still solid

At the end of the measurements the test item was still solid. The measurement with the capillary method confirmed the results of the DSC-measurements concerning the melting and boiling behavior.

Conclusions:

The test item zinc methacrylate has no melting and boiling point at atmospheric pressure (1013 hPa). The test item decomposes firstly at a temperature of > 200°C. The measurement with the capillary method confirmed the results of the DSC-measurements concerning the melting and boiling behavior.

Executive summary:

This study was performed in order to determine the thermal stability as well as the melting/boiling point of Zinc methacrylate according to the EU Method A.2 and OECD 103 and 113. In this test, the thermal stability and the boiling temperature of the test item were investigated by DSC (differential scanning calorimetry). With this method the difference in energy input into the test item and a reference material as a function of temperature was recorded, while the substance and reference material were subjected to the same temperature program. The prepared crucibles (crucible with test item and reference crucible) were placed in the DSC apparatus. To verify the results of the DSC-measurement six additional measurements with the capillary method (Apparatus: Büchi melting Point B-540) were performed. The test item zinc methacrylate has no melting and boiling point at atmospheric pressure (1013 hPa). The test item decomposes firstly at a temperature of > 200 °C. The measurement with the capillary method confirmed the results of the DSC-measurements concerning the melting and boiling behavior. The result has been considered as reliable without restriction because the test was performed in compliance with OECD and EU guidelines giving scientifically valid results (Moller, 2012).

Description of key information

The test item zinc methacrylate has no melting and boiling point at atmospheric pressure (1013 hPa). The test item decomposes at a temperature >200°C. The measurement with the capillary method confirmed the results of the DSC-measurements concerning the melting and boiling behaviour.

Key value for chemical safety assessment

Melting / freezing point at 101 325 Pa:

200 °C

Additional information

The thermal stability and the melting/boiling point of zinc methacrylate were determined according to the EU Method A.2 and OECD 103 and 113. In this test, the thermal stability and the boiling temperature of the test item were investigated by DSC (differential scanning calorimetry). To verify the results of the DSC-measurement six additional measurements with the capillary method (Apparatus: Büchi melting Point B-540) were performed (Moller, 2012).