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.

02 · Identifiers

Di-tert-butyl peroxide identifiers and molecular data

Di-tert-butyl peroxide CAS number and EC number

CAS number110-05-4
EC number203-733-6
Index number (CLP Annex VI)617-001-00-2

Di-tert-butyl peroxide molecular formula and molecular weight

Molecular formulaC8H18O2
Molecular weight146.23 g/mol
Chemical class Flammable agents - 3rd degree

03 · GHS classification

Di-tert-butyl peroxide hazard classification

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

Di-tert-butyl peroxide pictograms and signal word

Signal wordDanger

Di-tert-butyl peroxide hazard class and category

GHS hazard classes Di-tert-butyl peroxide falls into
Hazard class Category From code Pictogram
Flammable liquids GHS chapter 2.6 Category 2 H225 GHS02
Organic peroxides or Self-reactive substances and mixtures Category Type C and D or Type E and F H242 GHS02
Germ cell mutagenicity GHS chapter 3.5 Category 2 H341 GHS08

Where two values are shown with “or”, the hazard statement is shared by more than one category or by more than one class, and the code alone does not say which. H272, for example, belongs to oxidising liquids and to oxidising solids — the physical state decides. The binding answer for a specific entry is in the CLP Annex VI table itself.

Di-tert-butyl peroxide hazard statements (H-codes)

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>.

This page lists only the codes assigned to Di-tert-butyl peroxide. The full reference lives on the hazard statements hub, the precautionary statements hub and the GHS pictograms hub.

Safety Data Sheet

Getting an SDS for Di-tert-butyl peroxide

A Safety Data Sheet is written for a product, not for a substance: the supplier of the grade you actually buy issues it, so two suppliers of Di-tert-butyl peroxide issue two different sheets. That is why there is no single authoritative SDS for a substance to download — what there is, is the job of collecting the sheets for the products you hold and keeping them current as suppliers revise them.

04 · Precautionary statements

Di-tert-butyl peroxide precautionary statements

CLP Annex VI assigns 9 precautionary statements to Di-tert-butyl peroxide. They are grouped the way a label groups them: what to do before handling, what to do when something has already happened, how to store it and how to dispose of it.

Response

What to do once exposure, spillage or fire has already happened.

Storage

How the container has to be kept between uses.

Reading the notation. is a blank the supplier fills in — not a truncated sentence.· [square brackets] mark a part printed only when it applies.

05 · Names in the regulation

Di-tert-butyl peroxide name in 23 EU languages

CLP Annex VI Part 3 is published in every language edition of the regulation, and the identification column is written out in each of them. Nothing below is translated by us: each line is the name as that edition prints it. Under Art. 18(2) the substance name from Annex VI is a lawful product identifier, so this is the wording to put on a label going to that market — and where the cell lists several designations, any one of them qualifies.

Language Name in CLP Annex VI Part 3
Bulgarian български ди- трет -бутилпероксид
Spanish español Peróxido de di- terc -butilo
Czech čeština di- terc -butylperoxid
Danish dansk di- tert -butylperoxid
German Deutsch Di- tert -butylperoxid
Estonian eesti di- tert -butüülperoksiid
Greek ελληνικά δι- tert -βουτυλοϋπεροξείδιο
English English di- tert -butyl peroxide
French français péroxyde de di- tert -butyle
Croatian hrvatski di- tert -butil peroksid
Italian italiano perossido di butile terziario terz -butil-perossido
Latvian latviešu di- terc -butilperoksīds
Lithuanian lietuvių di- tret -butilperoksidas
Hungarian magyar di( terc -butil)-peroxid
Maltese Malti perossidu ta’ di-terz-butil
Dutch Nederlands di- tert -butylperoxide
Polish polski nadtlenek di-tert-butylu
Portuguese português peróxido de di- terc -butilo
Romanian română peroxid de di- terț -butil
Slovak slovenčina di- terc -butylperoxid
Slovenian slovenščina di- terc -butil peroksid
Finnish suomi di- tert -butyyliperoksidi
Swedish svenska di- tert -butylperoxid

All 23 language editions of Annex VI carry this entry. Irish is the twenty-fourth official EU language and has no line here for a different reason: no consolidated CLP text has ever been published in Irish, so there is no Irish edition of Annex VI to quote a name from. Source: consolidated CLP, CELEX 02008R1272, language editions. © European Union, https://eur-lex.europa.eu — only the electronic Official Journal of the European Union is authentic.

06 · Label elements

Di-tert-butyl peroxide GHS label elements

Everything CLP Annex VI fixes for Di-tert-butyl peroxide, laid out the way it appears on a label. The greyed lines are the parts only the supplier can fill in.

GHS02 Flame pictogramGHS08 Health hazard pictogram

Danger

Di-tert-butyl peroxide

  • Highly flammable liquid and vapour.
  • Heating may cause a fire.
  • Suspected of causing genetic defects <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
  • Obtain special instructions before use.
  • Keep away from heat, hot surfaces, sparks, open flames and other ignition sources. No smoking.
  • Keep container tightly closed.
  • Use explosion-proof [electrical/ventilating/lighting/…] equipment.
  • Use only non-sparking tools.
  • Wear protective gloves/protective clothing/eye protection/face protection/hearing protection/
  • IF exposed or concerned:
  • Get medical advice/attention.
  • Store in a well-ventilated place.

Supplier name, address and telephone number· Product identifier·Nominal quantity

Need this as an actual label? Open Di-tert-butyl peroxide in the GHS label constructor →

07 · Health hazards

Di-tert-butyl peroxide health hazards and exposure limits

Di-tert-butyl peroxide hazard summary

Caused muscle weakness and ataxia after intraperitoneal lethal-dose studies of rats; Mild irritant effect when administered into eyes of rabbits; [RTECS] Fire hazard; Strong oxidizer; [Hawley] A skin and mucous membrane irritant; Corrosive to eyes; [HSDB] An eye and respiratory tract irritant; [ICSC] May cause irritation; [MSDSonline]

Source: Haz-Map, Information on Hazardous Chemicals and Occupational Diseases

08 · 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.

Di-tert-butyl peroxide boiling point

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

Di-tert-butyl peroxide melting point

Property Value Conditions Source
Melting point -40 °C (-40 °F) HSDB
-29 °C (-20.2 °F) HSDB

Di-tert-butyl peroxide density

Property Value Conditions Source
Density 0.8 g/cm³ ICSC
0.704 g/cm³ at 20 °C CAMEO
0.791 g/cm³ at 25 °C HSDB

Di-tert-butyl peroxide solubility

Property Value Conditions Source
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

Di-tert-butyl peroxide vapor pressure

Property Value Conditions Source
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

Di-tert-butyl peroxide flash point

Property Value Conditions Source
Flash point 1 °C (33.8 °F) HSDB
18.33 °C (65 °F) HSDB
12 °C (53.6 °F) HSDB

Di-tert-butyl peroxide lower explosive limit (LEL)

Property Value Conditions Source
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

Di-tert-butyl peroxide vapor density

Property Value Conditions Source
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.

09 · Fire and explosion

Di-tert-butyl peroxide fire and explosion behaviour

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.

Di-tert-butyl peroxide fire potential

Flammable liquid.

Source: Hazardous Substances Data Bank (HSDB)

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

10 · Handling and storage

Di-tert-butyl peroxide storage and handling

Di-tert-butyl peroxide safe storage

Fireproof. Separated from combustible substances and reducing agents. Cool. Well closed.

Source: ILO-WHO International Chemical Safety Cards (ICSCs)

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)

Di-tert-butyl peroxide incompatible materials

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

Source: Hazardous Substances Data Bank (HSDB)

Di-tert-butyl peroxide 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 →

11 · Questions

Di-tert-butyl peroxide — frequently asked questions

What is the CAS number of Di-tert-butyl peroxide?

The CAS number of Di-tert-butyl peroxide is 110-05-4. Its EC number is 203-733-6.

What is the chemical formula of Di-tert-butyl peroxide?

The molecular formula of Di-tert-butyl peroxide is C8H18O2 and its molecular weight is 146.23 g/mol.

What does a Di-tert-butyl peroxide label have to show?

Under CLP Annex VI the label for Di-tert-butyl peroxide carries the pictograms Flame and Health hazard and the signal word is Danger.

Is Di-tert-butyl peroxide flammable?

Yes. CLP Annex VI assigns Di-tert-butyl peroxide H225 and H242 — highly flammable liquid and vapour. The flash point reported for it is 1 °C (33.8 °F) (HSDB).

Is Di-tert-butyl peroxide a carcinogen?

CLP Annex VI records no harmonised carcinogenicity classification for Di-tert-butyl peroxide. Annex VI is a list of agreed classifications, not a list of substances found safe, so this is an absence of a classification rather than a clean bill of health.

What is the boiling point of Di-tert-butyl peroxide?

The boiling point reported for Di-tert-butyl peroxide is 111 °C (231.8 °F) (HSDB).

What is the melting point of Di-tert-butyl peroxide?

The melting point reported for Di-tert-butyl peroxide is -40 °C (-40 °F) (HSDB).

How should Di-tert-butyl peroxide be stored?

CLP Annex VI assigns Di-tert-butyl peroxide the storage statement P403. 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. (Hazardous Substances Data Bank (HSDB))

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