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

Bis(α,α-dimethylbenzyl) peroxide

Bis(α,α-dimethylbenzyl) peroxide is crystals from ethanol.

CAS 80-43-3 C18H22O2 270.4 g/mol Danger

01 · Identification

What Bis(α,α-dimethylbenzyl)… is

Bis(α,α-dimethylbenzyl) peroxide is crystals from ethanol. Its molecular formula is C18H22O2 and its molecular weight is 270.4 g/mol. It boils at 130 °C, melts at 40 °C.

Under the GHS it carries the signal word Danger.

CAS number80-43-3
EC number201-279-3
Index number617-006-00-X
Molecular formulaC18H22O2
Molecular weight270.4 g/mol

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 Bis(α,α-dimethylbenzyl)…
CodeHazard statement
H242 Heating may cause a fire.
H360D May damage the unborn child.
H315 Causes skin irritation.
H319 Causes serious eye irritation.
H411 Toxic to aquatic life with long lasting effects.

Precautionary statements: P264, P273, P280, P302, P305, P313, P332, P337, P338, P352, P391, P501

03 · Physical and chemical properties

Bis(α,α-dimethylbenzyl)… 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 130 °C (266 °F) decomposes, at 760 mmHg CAMEO
100 °C (212 °F) at 0.2 mmHg (reduced pressure) HSDB
Melting point 40 °C (104 °F) HSDB
39 °C (102.2 °F) ICSC
Density 1.02 g/cm³ HSDB
1 g/cm³ ICSC
Solubility Solubility in water: none ICSC
less than 1 mg/mL at 73 °F (NTP, 1992) at 22.78 °C CAMEO
In water, 0.4 mg/L at 25 °C at 25 °C HSDB
Flash point 71.11 °C (160 °F) HSDB
71 °C (159.8 °F) ICSC
Lower explosive limit (LEL) Severe explosion hazard when shocked, exposed to heat, or by spontaneous chemical reaction. Organic peroxides HSDB
Vapor density 9.3 (air = 1) CAMEO

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

04 · Fire and explosion

Fire and explosion behaviour of Bis(α,α-dimethylbenzyl)…

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 Bis(α,α-dimethylbenzyl)…

Storage conditions

Store in original container. Keep container tightly closed in a dry and well-ventilated place. Recommended storage temperature 2-8 °C.

Source: Hazardous Substances Data Bank (HSDB)

Incompatible materials

Reacts violently with acids, bases, reducing agents, and heavy metals.

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 Bis(α,α-dimethylbenzyl)… in the storage compatibility matrix →

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