Bisisobutyryl peroxide

Vapour pressure

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

vapour pressure

Type of information:

other: summary of results

Adequacy of study:

supporting study

Reliability:

3 (not reliable)

Rationale for reliability incl. deficiencies:

other: Summary of previous measured data, no information on purity in this report.

Qualifier:

no guideline followed

Principles of method if other than guideline:

DSC (Differential Scanning Calorimeter)

GLP compliance:

no

Type of method:

other: DSC (Differential Scanning Calorimeter)

Temp.:

34 °C

Vapour pressure:

3.1 mBar

Temp.:

51 °C

Vapour pressure:

8.5 mBar

3.1 mBar = 310 Pa

8.5 mBar = 850 Pa

Conclusions:

The vapour pressure of bisisobutyryl peroxide is 310 Pa at 34°C, 850 Pa at 51°C . The high vapour pressure is caused by the solvent, Naphtha (petroleum), hydrotreated heavy.

Executive summary:

The high vapour pressure is caused by the solvent, Naphtha (petroleum), hydrotreated heavy.

The vapour pressure of bisisobutyryl peroxide is 310 Pa at 34°C, 850 Pa at 51°C .

Reference 2

Endpoint:

vapour pressure

Type of information:

calculation (if not (Q)SAR)

Remarks:

estimated by calculation

Adequacy of study:

key study

Study period:

September 2012

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Calculation from the measurement of the diluted product is the only possibility to estimate the vapour pressure of the pure substance, because the pure substance is too dangerous to handle and the thermal instability of the substance.

Qualifier:

according to guideline

Guideline:

other: ASTM 1782-08, Standard test method for determining vapour pressure by Thermal Analysis, 2008

Deviations:

yes

Remarks:

See for details Principles of method if other than guideline

Principles of method if other than guideline:

The vapour pressure of bisisobutyryl peroxide 100% at 20°C is calculated from experimental data on bisisobutyryl peroxide CAS#: 3437-84-1, 30% in isododecane and from the experimental data of isododecane CAS#: 93685-81-5.
This test method is not included into EC Regulation 761/2009, Guideline A.4 Vapour Pressure, nor into OECD Guideline 104 Vapour pressure, . Nevertheless, this method was taken because for substances which are thermally unstable and contain impurities it is a more suitable method than the other listed in the above-mentioned guidelines. It is expected that this method will be included into EC Guideline A.4 in the near future. A request for inclusion was sent to the Dutch National Coordinator for EC Test Methods. See:Letter to RIVM Bilthoven, the Netherlands, subject: IVM vapour pressure, by G.B. Boerdijk, 2.412.971, dated February 2, 2010.

GLP compliance:

no

Type of method:

other: calculation

Temp.:

20 °C

Vapour pressure:

1.2 mBar

Temp.:

20 °C

Vapour pressure:

0.12 kPa

Remarks on result:

other: Calculation from mBar.

Vapour pressure measurement were carried out on bisisobutyryl peroxide 30% in isododecane, see

Vapour pressures of organic peroxides measurements for the AKZO Nobel site in Pasadena, Doc. Code: PCS 200000009, Safety-detail Report, G.B. Boerdijk, 21-01-2000.

Data of the vapour pressure of isododecane is also collected from reference above.

 

Results were fitted in the Antoine equation:

 

Where             P           is the vapour pressure in mBar

                       A, B, C  are constants

                       T           is the absolute temperature in Kelvin.

 

Table 1            Overview of Antoine data based on values in mBar.

 

Component	A	B	C	Temp. range of investigations (°C)
test substance   isododecane	8.868   7.036	2573.1   1515.1	0   -74.7	34 – 51   40 - 180

 

Vapour pressure of the test substance at 20°C is calculated according to this information: 1.24 mBar

Vapour pressure of isododecane at 20°C is 1.26 mBar.

 

The molecular weight of bisisobutyryl peroxide is 174.2, the molecular weight of isododecane is 170.3.

An amount of 1 kg of the test substance contains 300 g bisisobutyryl peroxide, this corresponds with 1.722 Mole bisisobutyryl peroxide.

The amount of isododecane is 700 gram, or 4.110 Mole isododecane.

The Mole fraction bisisobutyryl peroxide and isododecane is respectively 0.295 and 0.705.

 

Vapour pressure of bisisobutyryl peroxide at 20°C is then calculated according to Raoult’s law:

 

Mole fraction bisisobutyryl peroxide* vapour pressurebisisobutyryl peroxide+ Mole fraction isododecane * vapour pressure isododecane =

vapour pressure ofthe test substance.

 

0.295 * vapour pressure bisisobutyryl peroxide+ 0.705 * 1.26 = 1.24 mBar.

 

Vapour pressure of bisisobutyryl peroxide at 20°C = 1.19 mBar or 0.12 kPa.

 

Conclusions:

The vapour pressure of pure bisisobutyryl peroxide at 20°C = 1.2 mBar or 0.12 kPa.

Executive summary:

The vapour pressure of bisisobutyryl peroxide 100% at 20°C was calculated from experimental data on bisisobutyryl peroxide CAS#: 3437-84-1, 30% in isododecane and from the experimental data of isododecane CAS#: 93685-81-5.

Vapour pressure measurements were carried out with DSC experiments at reduced pressure in accordance with ASTM E1782-08, Standard test method for determining vapour pressure by Thermal Analysis, March 1, 2008. The onset of boiling was measured as a function of the absolute pressure in the range of 0.31 to 0.85 kPa.

The vapour pressure of pure bisisobutyryl peroxide at 20°C = 1.2 mBar or 0.12 kPa.

Description of key information

The vapour pressure of pure bisisobutyryl peroxide at 20°C = 1.2 mBar or 0.12 kPa.

Key value for chemical safety assessment

Vapour pressure:

0.12 kPa

at the temperature of:

20 °C