N,N''-(methyl-m-phenylene)bis[N',N'-dimethylurea]

Density

Link to relevant study record(s)

Reference

Endpoint:

bulk density

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2011-11-03

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 109 (Density of Liquids and Solids)

GLP compliance:

no

Type of method:

pycnometer method

Key result

Type:

bulk density

Density:

1.23 g/cm³

Temp.:

20 °C

Remarks on result:

other: The temperature inside the pycnometer chamber was approximately 27.4° C (± 2 K). A correction was applied to calculate the density at 20°C.

Table1: Density of TDI-Urone at 27.4°C

Test		# 1	# 2
mass [g] *)		1.3926	1.5372
temperature	run	27.4°C	27.4°C
volume [cm³]	1 2 3 4 5	1.1417 1.1395 1.1346 1.1375 1.1378	1.2499 1.2459 1.2474 1.2488 1.2491
average volume [cm³]	(of last five runs)	1.1382	1.2482
density [g/cm³]		1.2235	1.2315

For solid organic compounds the cubic thermal expansion coefficient  is in the range of = 20 - 45 x 10^-5K^-1(D'Ans Lax, Taschenbuch für Chemiker und Physiker, Band I, 3.Aufl., 1967). Using an average value (mode) of (c)= 30 x 10^-5K^-1the volume (VT) measured at the temperature of the chamber TCh is extrapolated to the volume (V20°) at 20°C according to the formulae:

V20° = V_T-deltaV_T-20, and

delta V_T-20° = V_T.. (T_Ch-20°)

Since the temperature inside the pycnometer chamber was approximately 27.4° C (± 2 K) a correction was applied to calculate the density at 20°C.

Table 2: Density of TDI-Urone at 20°C

Test		# 1	# 2
temperature difference [°C]	TCh– 20°C	7.4	7.4
volume difference [cm³]	for delta T	0.0025	0.0028
corrected volume [cm³]	(20°C)	1.1357	1.2454
density [g/cm³]	(20°C)	1.2262	1.2343

Conclusions:

The relative density of the test substance extrapolated at 20°C is:
ρ20 = 1.230 g/cm³ or 1230 kg/m³ .

Executive summary:

The density of TDI-Urone at 20°C was determined according guideline OECD 109 by gas displacement pycnometry. It was determined to be 1.230 g/cm³ or 1230 kg/m³.

Description of key information

The density of the test substance at 20°C is:
ρ20 = 1.230 g/cm³ or 1230 kg/m³.

Additional information

There are two literature sources reporting the density of TDI-Urone.

In one study the density of TDI-Urone at 20°C was determined according to Guideline OECD 109 by gas displacement pycnometry. It is reported to be 1.230 g/cm³ or 1230 kg/m³.

Furthermore the density of TDI-Urone is reported in the Safety Data Sheet by Degussa to be 1.04 g/cm³.

The experimental result is chosen as key value because it is more reliable than the value in the SDS.