(1R)-1-[(4R,4aR,8aS)-2,6-bis(3,4-dimethylphenyl)tetrahydro[1,3]dioxino[5,4-d][1,3]dioxin-4-yl]ethane-1,2-diol

Vapour pressure

Administrative data

Endpoint:

vapour pressure

Type of information:

experimental study

Adequacy of study:

key study

Study period:

5th March 1993 to 1st October 1993

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Study conducted in compliance with agreed protocols, with no or minor deviations from standard test guidelines and/or minor methodological deficiencies, which do not affect the quality of the relevant results.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1993

Report date:

1993

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

EU Method A.4 (Vapour Pressure)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

OECD Guideline 104 (Vapour Pressure Curve)

Deviations:

no

Principles of method if other than guideline:

The vapour pressure (A4) was performed according to the gas saturation method instead of one of the three methods described in the protocol-Directive EEC 92/69 was followed, instead of EEC 84/449 (update).

GLP compliance:

yes (incl. QA statement)

Type of method:

gas saturation method

Test material

Test material information

Constituent 1

Results and discussion

Vapour pressure

Vapour pressure 1

Temp.:

373.15 K

Vapour pressure:

0.796 other: mPa

Vapour pressure 2

Temp.:

363.15 K

Vapour pressure:

0.555 other: mPa

Vapour pressure 3

Temp.:

298.15 K

Vapour pressure:

0 Pa

Remarks on result:

other: 25 °C value calculated from above first two measurements

Transition / decomposition

Transition / decomposition:

no

Any other information on results incl. tables

The vapour pressure of a substance is defined as the saturation pressure of the vapour at thermodynamic equilibrium with the solid or liquid phase of the substance at a fixed temperature of the entire system. The vapour pressure so defined is a function of temperature only. The SI unit of pressure is the Pascal (Pa).

 

The vapour pressure, Vp, is related to the observed saturated gas concentration by the relationship:

 

Vp = (Weight of TA vaporised (g) x Temperature (K) x 8.314) / (Volume of saturated gas (m³) x Molecular weight) Pa

 

The vapour pressure-temperature relationship is represented as thedependence of log₁₀vapour pressure versus reciprocal temperature in Kelvin, as expressed in the Clausius-Clapeyron equation. The linearity of such a representation stems from the relative insensitivity of heats of vaporisation/sublimation to temperature changes. The following vapour pressure relationship:

 

Log₁₀Vp (Pa) = (Slope / Intercept Temperature (K)) + Intercept

 

is thus used to determine, by extrapolation, the vapour pressure at298.15K (25°C).

 

The slope and intercept of the vapour pressure curve are estimated byan unweighed least squares statistical treatment of all the data points.

 

The following were the mean determined vapour pressures:

 

Vp 100°C:                                                0.796 mPa

Vp 90°C:                                                  0.555 mPa

 

The derived line of Log₁₀Vp (Y) against 1/T(K) (X) was determined from the 5 individual results:

 

Mean: Y = -4401.1 x1/T + 8.852. Correlation coefficient -0.857

 

Temperature 100 °C	Run time 191 hours
Channel reference	1	2	3	4
Nominal flow (mL/min)	17	23	28	32
Total sampled flow (mL)	192253	259001	316887	273242
Mass Millad 3988 collected (µg)	35.4	*	40.0	2.28
Vapour pressure (mPa)	1.38	*	0.945	0.063
Mean Vp (mPa)	0.796

 

* No sample detected

 

 

 

Temperature 90 °C	Run time 138 hours
Channel reference	1	2	3	4
Nominal flow (mL/min)	17	23	28	32
Total sampled flow (mL)	140524	189948	230962	266843
Mass Millad 3988 collected (µg)	*	16.3	20.8	14.1
Vapour pressure (mPa)	*	0.624	0.656	0.386
Mean Vp (mPa)	0.555

 

* No sample detected

Applicant's summary and conclusion

Conclusions:

The vapour pressure values at a range of temperatures were as shown below:
Vp = 0.796 mPa at 373.15 K
Vp = 0.555 mPa at 363.15 K
The calculated value of vapour pressure based upon the above readings is:
Vp = 1.23 x 10E-6 Pa at 298.15 (25 °C)

Executive summary:

In a vapour pressure study (13193), the vapour pressure of the test material was calculated to be 1.23 x 10E-6 Pa at 25 °C, according to Method A4 of Commission Directive 92/69/EEC.