2,4,6-trimethyl-2,4,6-tris(3,3,3-trifluoropropyl)cyclotrisiloxane

Vapour pressure

Link to relevant study record(s)

Reference

Endpoint:

vapour pressure

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2012-05-24 to 2012-05-25

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 104 (Vapour Pressure Curve)

Deviations:

no

GLP compliance:

yes

Type of method:

static method

Key result

Test no.:

#1

Temp.:

20 °C

Vapour pressure:

75.6 Pa

Key result

Test no.:

#2

Temp.:

25 °C

Vapour pressure:

88 Pa

Table 1: Determination of the vapour pressure of 2,4,6-trimethyl-2,4,6-tris(3,3,3-trifluoropropyl)cyclotrisiloxane during the static vapour pressure experiment.

Test Temperature (^oC)	Temperature (1/T)	Vapour Pressure (torr)	Mean Vapour Pressure (Pa)	Mean log Pa
69.5	0.00292	2.0
	0.00292	2.0
	0.00292	2.0
	Mean (SD):	2.0 (0.00)	267	5.59
75.0	0.00287	2.2
	0.00287	2.2
	0.00287	2.5
	0.00287	2.2
	Mean (SD):	2.3 (0.150)	303	5.72
79.5	0.00284	2.6
	0.00284	2.8
	0.00284	2.8
	Mean (SD)	2.7 (0.115)	364	5.90
84.0	0.00280	3.4
	0.00280	2.4
	0.00280	2.9
	0.00280	2.9
	0.00280	2.8
	0.00280	3.0
	Mean (SD)	2.9 (0.322)	387	5.95
90.0	0.00275	3.2
	0.00275	3.0
	0.00275	3.2
	0.00275	3.0
	Mean (SD):	3.1 (0.115)	413	6.02
94.0	0.00272	3.1
	0.00272	3.2
	0.00272	3.2
	0.00272	3.8
	0.00272	3.6
	0.00272	3.0
	0.00272	3.2
	0.00272	3.4
	Mean (SD):	3.3 (0.270)	442	6.09
98.0	0.00269	4.1
	0.00269	3.8
	0.00269	3.8
	0.00269	3.6
	0.00269	3.9
	0.00269	3.7
	Mean (SD):	3.8 (0.172)	509	6.23

NOTE: Numbers may vary slightly due to rounding. Table includes all values to show stability over all measurements.

Table 2: summary of results

Temperature (ºC)	Temperature (1/T)	Pressure (Torr)	Pressure (Pa)	log Pa^a
69.5	0.00293	2.0	267	5.59
75.0	0.00288	2.3	303	5.72
79.5	0.00284	2.7	364	5.90
84.0	0.00281	2.9	387	5.96
90.0	0.00276	3.1	413	6.02
94.0	0.00273	3.3	442	6.09
98.0	0.00270	3.8	509	6.23

^a          Results presented are the natural log of the pressure reported in Pascals.

Conclusions:

A measured vapour pressure of 75.6 Pa at 20°C and 88 Pa at 25°C were determined for the substance in accordance with OECD 104 and in compliance with GLP. The result is considered reliable.

Description of key information

Vapour Pressure [2,4,6-trimethyl-2,4,6-tris(3,3,3-trifluoropropyl)cyclotrisiloxane]: 88 Pa at 25°C (OECD 104)

Key value for chemical safety assessment

Vapour pressure:

88 Pa

at the temperature of:

25 °C

Additional information

Measured vapour pressure values of 75.6 Pa at 20°C and 88 Pa at 25°C were determined for the substance using the static method in accordance with OECD Test Guideline 104 and in compliance with GLP. The result is considered to be reliable.

Predicted vapour pressure values of 2.5E-04 Pa at 25°C and 1.3 Pa at 25°C are estimated for the intermediate degradation product (1,5-dihydroxy-1,3,5-trimethyl-1,3,5-tris(3,3,3-trifluoropropyl)trisiloxane) and ultimate degradation product ( 3,3,3-trifluoropropylmethysilanediol) respectively.