N,N'-methylenedistearamide

Vapour pressure

Link to relevant study record(s)

Reference

Endpoint:

vapour pressure

Type of information:

experimental study

Adequacy of study:

key study

Study period:

12 Jun 2018 to 15 Jun 2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 104 (Vapour Pressure Curve)

Version / remarks:

23 March 2006

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method A.4 (Vapour Pressure)

Version / remarks:

30 May 2008

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

effusion method: vapour pressure balance

Key result

Temp.:

ca. 25 °C

Vapour pressure:

< 0.002 Pa

Remarks on result:

other: extrapolated value

Among all the Runs, Run 10 was chosen because the sample had been under vacuum for the longest period prior to this run and so degassing would have been the most complete. The reading at 133 ºC (406.15 K) was chosen because this is the data point which gives the highest estimated vapor pressure at any given temperature when a slope of –1000 K is imposed upon it. The value of –1000 K is an in-house value and is the shallowest slope observed whilst determining the vapor pressure on a wide range of samples using the vapor pressure balance method. Extrapolation to 25 ºC gave a vapor pressure of 2.13 x 10-3 Pa which has been taken as a maximum for this material.

Table: Vapor Pressure Data (Run 10):

Temperature (ºC)	Temperature (K)	Reciprocal Temperature (K^-1)	Mass Difference (μg)	Mass Difference (kg)	Vapor Pressure (Pa)	Log10Vp
130	403.15	0.002480	9.09	9.090e-09	0.01262	-1.89894
131	404.15	0.002474	9.98	9.980e-09	0.01385	-1.85855
132	405.15	0.002468	9.39	9.390e-09	0.01304	-1.88472
133	406.15	0.002462	11.98	1.198e-08	0.01663	-1.77911
134	407.15	0.002456	9.19	9.190e-09	0.01276	-1.89415
135	408.15	0.002450	11.78	1.178e-08	0.01635	-1.78648
136	409.15	0.002444	9.68	9.680e-09	0.01344	-1.87160
137	410.15	0.002438	10.38	1.038e-08	0.01441	-1.84134
138	411.15	0.002432	9.98	9.980e-09	0.01385	-1.85855
139	412.15	0.002426	12.78	1.278e-08	0.01774	-1.75105
140	413.15	0.002420	12.78	1.278e-08	0.01774	-1.75105

The test item did not change in appearance under the conditions used in the determination.

No statistical analyses were performed because the balance readings were too low and variable for a line of best fit to have any meaning. Instead it was considered more appropriate to impose a regression slope on a chosen data point to provide an estimate of the maximum value for the vapor pressure at 25 ºC.

Conclusions:

The vapor pressure of the test item has been determined to be less than 0.002 Pa at 25 ºC (extrapolated value).

Executive summary:

The vapor pressure of test item was determined by using the vapor pressure balance method, designed to be compatible with OECD TG 104 and in compliance with GLP. Extrapolation to 25 ºC gave a vapor pressure of 0.00213 Pa which has been taken as a maximum for this material.

Description of key information

Vapour pressure less than 0.002 Pa at 25 ºC, compatible with OECD 104, vapor pressure balance method, Ford 2018

Key value for chemical safety assessment

Vapour pressure:

0.002 Pa

at the temperature of:

25 °C