Provenance

Reference data from EU CLP Annex VI and published regulations — verify against your supplier's SDS before use.

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Substance profile

Di-tert-butyl peroxide

Di-tert-butyl peroxide is a clear, water-white liquid.

CAS 110-05-4 C8H18O2 146.23 g/mol Danger

01 · Identification

What Di-tert-butyl peroxide is

Di-tert-butyl peroxide is a clear, water-white liquid. Its molecular formula is C8H18O2 and its molecular weight is 146.23 g/mol. It boils at 111 °C, melts at -40 °C.

Under the GHS it carries the signal word Danger. It is classed as flammable agents - 3rd degree.

CAS number110-05-4
EC number203-733-6
Index number617-001-00-2
Molecular formulaC8H18O2
Molecular weight146.23 g/mol
Chemical class Flammable agents - 3rd degree

02 · GHS classification

Hazards and label elements

Harmonised classification under CLP Annex VI. This is the legally binding classification in the EU; other jurisdictions may differ.

Signal wordDanger
Hazard statements assigned to Di-tert-butyl peroxide
CodeHazard statement
H225 Highly flammable liquid and vapour.
H242 Heating may cause a fire.
H341 Suspected of causing genetic defects <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.

Precautionary statements: P201, P210, P233, P241, P242, P280, P308, P313, P403

03 · Physical and chemical properties

Di-tert-butyl peroxide properties

Every value is shown with the conditions it was measured under and the source it came from. Where sources disagree, all values are listed rather than one being picked — the difference is usually a different form of the substance, not an error.

Property Value Conditions Source
Boiling point 111 °C (231.8 °F) HSDB
111.11 °C (232 °F) at 760 mmHg CAMEO
111 °C (231.8 °F) at 760 mmHg DOE PAC
Melting point -40 °C (-40 °F) HSDB
-29 °C (-20.2 °F) HSDB
Density 0.8 g/cm³ ICSC
0.704 g/cm³ at 20 °C CAMEO
0.791 g/cm³ at 25 °C HSDB
Solubility Insoluble in water HSDB
In water, 1.71 mg/L at 20 °C, pH 8.1 at 20 °C HSDB
In water, 100 mg/L at 25 °C at 25 °C HSDB
Vapor pressure 19.51 mmHg at 20 °C CAMEO
19.5016 mmHg at 20 °C ICSC
25.1 mmHg at 25 °C, calculated from experimentally derived coefficients HSDB
Flash point 1 °C (33.8 °F) HSDB
18.33 °C (65 °F) HSDB
12 °C (53.6 °F) HSDB
Lower explosive limit (LEL) Vapor/air mixtures are explosive. HSDB
Prevention: Closed system, ventilation, explosion-proof electrical equipment and lighting. Do not use compressed air for filling, discharging, or handling. HSDB
Vapor density 5.03 (air = 1) HSDB
5 (air = 1) ICSC

Values compiled from PubChem Laboratory Chemical Safety Summary. Temperatures converted to Fahrenheit for reference.

04 · Fire and explosion

Fire and explosion behaviour of Di-tert-butyl peroxide

These are descriptions rather than measured values, so they are kept out of the table above and quoted here with the source that reported them.

Fire and explosion

Seven organic peroxides were tested for propagation and power of explosion, and for shock sensitivity. Tert-butylperoxybenzoate and dibenzoylperoxide showed high shock sensitivity and explosive powers of 40 and 25% of TNT respectively. Di-tert-butylperoxide showed medium sensitivity and a power of 30% TNT. Cumyl hydroperoxide (80% in cumene), dibenzoylperoxide (75% in water), dicumyl peroxide and dilauroyl peroxide did not propagate explosion.

Source: HSDB

05 · Handling and storage

Storing and handling Di-tert-butyl peroxide

Storage conditions

Store in original container. Keep container tightly closed in a dry and well-ventilated place. Containers which are opened must be carefully resealed and kept upright to prevent leakage. Recommended storage temperature 2 - 8 °C. Storage class (TRGS 510): Organic peroxides and self-reacting hazardous materials.

Source: Hazardous Substances Data Bank (HSDB)

Incompatible materials

Incompatible materials: Strong reducing agents, powdered metals, strong bases.

Source: Hazardous Substances Data Bank (HSDB)

Reactivity

The explosive instability of the lower dialkyl peroxides (e.g., dimethyl peroxide) and 1,1-bis-peroxides decreases rapidly with increasing chain length and degree of branching, the di-tert-alkyl derivatives being amongst the most stable class of peroxides. Though many 1,1-bis-peroxides have been reported, few have been purified because of the higher explosion hazards compared with the monofunctional peroxides. It is unlikely that this derivative would be particularly unstable compared to other peroxides in its class [Bretherick 2nd ed., p 44 1979].

Source: CAMEO Chemicals

Planning storage for a mix of chemicals? Check Di-tert-butyl peroxide in the storage compatibility matrix →

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