Reaction mass of 4-methylpentane-2,2-diyl dihydroperoxide, dioxybis-4-methylpentane-2,2-diyl dihydroperoxide and methylisobutylketon

Vapour pressure

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

vapour pressure

Type of information:

(Q)SAR

Adequacy of study:

weight of evidence

Study period:

2015-12-16

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

results derived from a valid (Q)SAR model and falling into its applicability domain, with adequate and reliable documentation / justification

Justification for type of information:

please refer to attached QMRF/QPRF

Qualifier:

according to guideline

Guideline:

other: ECHA Guidance on IR/CSA Chapter R.6

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: REACH Annex XI section 1.3

Deviations:

no

Principles of method if other than guideline:

Estimation of vapour pressure using the Antoine method of MPBPwin v1.43

GLP compliance:

no

Key result

Temp.:

25 °C

Vapour pressure:

0.129 mm Hg

Remarks on result:

other: The substance is within the applicability domain of the model.

Key result

Temp.:

25 °C

Vapour pressure:

17.2 Pa

Remarks on result:

other: The substance is within the applicability domain of the model.

MPBPVP (v1.43) Program Results:

===============================

Experimental Database Structure Match: no data

 

SMILES : CC(CC(C)C)(OO)OO

CHEM  : Hydroperoxide, 1,1'-(1,3-dimethylbutylidene)bis-

MOL FOR: C6 H14 O4

MOL WT : 150.18

------------------------ SUMMARY MPBVP v1.43 --------------------

Vapor Pressure Estimations (25 deg C):

(Using BP: 218.90 deg C (estimated))

(Using MP: 39.05 deg C (estimated))

VP: 0.111 mm Hg (Antoine Method)

: 14.8 Pa (Antoine Method)

VP: 0.0963 mm Hg (Modified Grain Method)

: 12.8 Pa (Modified Grain Method)

VP: 0.157 mm Hg (Mackay Method)

: 20.9 Pa (Mackay Method)

Selected VP: 0.0963 mm Hg (Modified Grain Method)

: 12.8 Pa (Modified Grain Method)

Subcooled liquid VP: 0.129 mm Hg (25 deg C, Mod-Grain method)

: 17.2 Pa (25 deg C, Mod-Grain method)

 

Conclusions:

The vapour pressure of Hydroperoxide, 1,1'-(1,3-dimethylbutylidene)bis- was estimated to be 17.2 Pa at 25 °C.

Executive summary:

The vapour pressure was calculated using MBBPWIN v1.43 as part of EPISuite v4.11 from US Environmental Protection Agency.

Using using MBBPWIN v1.43 the vapour pressure of the test item was calculated to be 17.2 Pa at 25 °C (EPI Suite, 2014).

 

The adequacy of a prediction depends on the following conditions:

a) the (Q)SAR model is scientifically valid: the scientific validity is established according to the OECD principles for (Q)SAR validation;

b) the (Q)SAR model is applicable to the query chemical: a (Q)SAR is applicable if the query chemical falls within the defined applicability domain of the model;

c) the (Q)SAR result is reliable: a valid (Q)SAR that is applied to a chemical falling within its applicability domain provides a reliable result;

d) the (Q)SAR model is relevant for the regulatory purpose.

 

For assessment and justification of these 4 requirements the QMRF and QPRF files were developed and attached to this study record.

 

Description of the prediction Model

The prediction model was descripted using the harmonised template for summarising and reporting key information on (Q)SAR models. For more details please refer to the attached QSAR Model Reporting Format (QMRF) file. 

 

Assessment of estimation domain

The assessment of the estimation domain was documented in the QSAR Prediction Reporting Format file (QPRF). Please refer to the attached document for the details of the prediction and the assessment of the estimation domain.

Reference 2

Endpoint:

vapour pressure

Type of information:

(Q)SAR

Adequacy of study:

weight of evidence

Study period:

2015-12-16

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

results derived from a valid (Q)SAR model and falling into its applicability domain, with adequate and reliable documentation / justification

Justification for type of information:

please refer to attached QMRF/QPRF documents

Qualifier:

according to guideline

Guideline:

other: ECHA Guidance on IR/CSA Chapter R.6

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: REACH Annex XI section 1.3

Deviations:

no

Principles of method if other than guideline:

Estimation of vapour pressure using the Antoine method of MPBPwin v1.43

GLP compliance:

no

Key result

Temp.:

25 °C

Vapour pressure:

0.001 mm Hg

Remarks on result:

other: The substance is within the applicability domain of the model.

Key result

Temp.:

25 °C

Vapour pressure:

0.075 Pa

Remarks on result:

other: The substance is within the applicability domain of the model.

Conclusions:

The vapour pressure of the test item was estimated to be 0.0752 Pa at 25 °C.

Executive summary:

The vapour pressure was calculated using MBBPWIN v1.43 as part of EPISuite v4.11 from US Environmental Protection Agency.

Using MBBPWIN v1.43 the vapour pressure of the test item was calculated to be 0.0752 Pa at 25 °C (EPI Suite, 2014).

 

The adequacy of a prediction depends on the following conditions:

a) the (Q)SAR model is scientifically valid: the scientific validity is established according to the OECD principles for (Q)SAR validation;

b) the (Q)SAR model is applicable to the query chemical: a (Q)SAR is applicable if the query chemical falls within the defined applicability domain of the model;

c) the (Q)SAR result is reliable: a valid (Q)SAR that is applied to a chemical falling within its applicability domain provides a reliable result;

d) the (Q)SAR model is relevant for the regulatory purpose.

 

For assessment and justification of these 4 requirements the QMRF and QPRF files were developed and attached to this study record.

 

Description of the prediction Model

The prediction model was descripted using the harmonised template for summarising and reporting key information on (Q)SAR models. For more details please refer to the attached QSAR Model Reporting Format (QMRF) file. 

 

Assessment of estimation domain

The assessment of the estimation domain was documented in the QSAR Prediction Reporting Format file (QPRF). Please refer to the attached document for the details of the prediction and the assessment of the estimation domain.

Description of key information

The vapour of the test item was estimated to be between 0.0752 Pa to 17.2 Pa at 25 °C. The vapour pressures of the stabilizer and methylisobutylketon were estimated to be between 100 Pa and 2640 Pa respectively. As a worst case a vapour pressure of 17.2 Pa at 25 °C can be assumed for Reaction mass of 4-methylpentane-2,2-diyl dihydroperoxide, dioxybis-4-methylpentane-2,2-diyl dihydroperoxide and methylisobutylketon.

 

Key value for chemical safety assessment

Vapour pressure:

17.2 Pa

at the temperature of:

25 °C

Additional information

The test method for determination of vapour pressure described in the test guideline A.4 of 2008/440/EC was replaced by a theory based evaluation as a reliable determination is not possible (the test item exist as solution (stabilizers) in solvents due to its reactivity).

 

The vapour pressure of the test item Reaction mass of 4-methylpentane-2,2-diyl dihydroperoxide, dioxybis-4-methylpentane-2,2-diyl dihydroperoxide and methylisobutylketon was calculated using EPIWIN (v. 4.10). The test item consists of three compounds, the monomer and the dimer of methyl-isobutylketone peroxide and 4-methylpentan-2-one.

 

The vapour pressure of the monomer (4-methylpentane-2,2-diyl dihydroperoxide) at 25 °C was estimated to be 17.2 Pa. The estimated vapour pressure of the dimer (dioxybis-4-methylpentane-2,2-diyl dihydroperoxide) at 25 °C was 0.0752 Pa. The vapour pressure of 4-methylpentan-2-one was reported in an weight of evidence approach to be at 2640 Pa at 25 °C (highest reported vapour pressure out of 3 independent literature sources, please refer to the published ECHA dossier).

 

Reaction mass of 4-methylpentane-2,2-diyl dihydroperoxide, dioxybis-4-methylpentane-2,2-diyl dihydroperoxide and methylisobutylketon is produced in different solvents only as pure substance is not stable and cannot be handled. As stabiliser Hydrocarbons, C4, 1,3-butadiene-free, polymerised., triisobutylene fraction, hydrogenated (Isododecan) was used. The vapour pressure of Isododecan was estimated to be 100 Pa at 25 °C (please refer to the disseminated ECHA dossier).

 

As a worst case a vapour pressure of 17.2 Pa at 25 °C can be assumed. From an environmental, ecotoxicological and toxicological view regarding the stabilizer and methylisobutylketon, it was considered that all hazardous or dangerous impacts are completely trigged by the main constituent 4-methylpentane-2,2-diyl dihydroperoxide, dioxybis-4-methylpentane-2,2-diyl dihydroperoxide.