1,1'-(1,1-dimethyl-3-methylene-1,3-propanediyl)bisbenzene

Vapour pressure

Link to relevant study record(s)

Reference

Endpoint:

vapour pressure

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Start of study: 2 May 2005. End of study: 2 June 2005

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Study performed according to guideline and GLP

Qualifier:

according to guideline

Guideline:

OECD Guideline 104 (Vapour Pressure Curve)

GLP compliance:

yes

Type of method:

gas saturation method

Temp.:

25 °C

Vapour pressure:

0.063 Pa

Vapor pressure measurement results:

Measurement temperature (°C)	Flow rate (mL/min)	Vapour pressure (Pa)
		Measured value	Average
40	20	2.91 x 10^-1	2.93 x 10^-1
	30	2.94 x 10^-1
	40	2.94 x 10^-1
50	20	7.27 x 10^-1	7.31 x 10^-1
	30	7.34 x 10^-1
	40	7.34 x 10^-1
60	20	1.73 x 10^0	1.72 x 10^0
	30	1.74 x 10^0
	40	1.71 x 10^0

Test results were comparable (repeat accuracy of 30% or less) regardless of measurement at different flow rates, and the carrier gas was thought to be saturated with the test substance.

Vapor Pressure at 25°C (Extrapolated Value) (Fig. 3).

Regression equation	logP (Pa) = -4014.49 x 1/T + 12.2868
Vapor pressure (25°C)	6.64 x 10^-2Pa

Blank test and others

In the results of the blank test, no peak was detected at the peak position of the test substance (Fig. 2-4). Test substance was not detected in the second trap (Fig. 2-4). Therefore, it was judged that the test substance was collected in the first trap under each condition.

Discussion:

Two peaks other than the test substance were detected in HPLC analysis (Peaks A and B in the order of elution). Since no peak was detected at the position of Peak A in HPLC analysis of the high concentration test substance solution (Reference 3), it was thought to be a conversionproduct produced during the test, but its structure is unknown. Peak B, however, was confirmed to a trace impurity in the obtained sample (Fig. 2-1 to 2-3, Reference 3). A supplemental test on the effects of this conversion product and impurity in the results of this test was conducted (Supplemental Test). When vapor pressure was measured at 25°C, no peak other than the test substance was detected on the HPLC chromatogram and the vapor pressure of the test substance was 6.34×10^-2Pa, similar to the result of this test.

Although a conversion product and impurity were detected at the same time as the test substance under the conditions of this test of 40°C and above, they were thought to have little effect on the vapor pressure of the test substance. Therefore, the results of this test were adopted as the vapor of the test substance.

Supplemental test:

Test conditions:

(1)    Test temperatures:              25°C

(2)    Flow rates:                         20, 30 and 40 mL/min

(3)    Replicates:                         1

(4)    Collection solvent:              Methanol 30 mL

(5)    Carrier gas:                        High purity nitrogen gas

The test apparatus, preparation of the vapor saturation column and analysis of test solutions were the same as in this test.

Vapor pressure measurement results:

Measurement temperature (°C)	Flow rate (mL/min)	Vapor pressure (Pa)
		Measured value	Average
25	20	5.16 x 10^-2	6.34 x 10^-2
	30	6.81 x 10^-2
	40	7.05 x 10^-2

Conclusions:

The vapor pressure of 2,4-diphenyl-4-methyl-1-pentene is 6.34 x 10^-2 Pa.

Description of key information

A study performed according to  OECD Guideline 104 reported a vapour pressure of 6.34 x 10^-2 Pa at 25°C

Key value for chemical safety assessment

Vapour pressure:

0.063 Pa

at the temperature of:

25 °C