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

N,N'-Diphenyl-P-Phenylenediamine

N,N'-Diphenyl-P-Phenylenediamine is colorless leaflets from alcohol; commercial grades are greenish-brown.

CAS 74-31-7 C18H16N2 260.3 g/mol Warning

01 · Identification

What N,N'-Diphenyl-P-Phenylenediami… is

N,N'-Diphenyl-P-Phenylenediamine is colorless leaflets from alcohol; commercial grades are greenish-brown. Its molecular formula is C18H16N2 and its molecular weight is 260.3 g/mol. It melts at 151 °C.

Under the GHS it carries the signal word Warning.

CAS number74-31-7
EC number200-806-4
Index number612-132-00-1
Molecular formulaC18H16N2
Molecular weight260.3 g/mol

Other names for N,N'-Diphenyl-P-Phenylenediami…

  • N,N'-diphenyl-1,4-benzenediamine

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 wordWarning
Hazard statements assigned to N,N'-Diphenyl-P-Phenylenediami…
CodeHazard statement
H317 May cause an allergic skin reaction.
H412 Harmful to aquatic life with long lasting effects.

Precautionary statements: P261, P272, P273, P280, P313, P333, P501

03 · Physical and chemical properties

N,N'-Diphenyl-P-Phenylenediami… 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 222.5 °C (432.5 °F) range, midpoint shown, at 0.5 mmHg (reduced pressure) HSDB
Melting point 150.5 °C (302.9 °F) range, midpoint shown HSDB
148.5 °C (299.3 °F) range, midpoint shown HSDB
148.61 °C (299.5 °F) range, midpoint shown CAMEO
Density 1.2 g/cm³ HSDB
1.21 g/cm³ CAMEO
Solubility Solubility in water: none ICSC
less than 1 mg/mL at 68 °F (NTP, 1992) at 20 °C CAMEO
Vapor pressure 6.35e-9 mmHg at 25 °C HSDB
1e-8 mmHg Haz-Map
Flash point 204.44 °C (400 °F) CAMEO
232 °C (449.6 °F) ICSC
Vapor density 9 (air = 1) HSDB
Critical temperature and pressure 632.85 °C (1171.1 °F) HSDB

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

04 · Source notes

Further notes on N,N'-Diphenyl-P-Phenylenediami…

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.

Solubility

Sol in monochlorobenzene, benzene, DMF, ether, chloroform, acetone, ethyl acetate, isopropyl acetate, glacial acetic acid. Slightly sol in alcohol. Almost insol in petr ether, water.

Source: HSDB

05 · Handling and storage

Storing and handling N,N'-Diphenyl-P-Phenylenediami…

Storage conditions

...MATERIALS WHICH ARE TOXIC AS STORED OR WHICH CAN DECOMP INTO TOXIC COMPONENTS DUE TO CONTACT WITH HEAT, MOISTURE, ACID, OR ACID FUMES, SHOULD BE STORED IN COOL, WELL-VENTILATED PLACE, OUT OF DIRECT RAYS OF SUN, AWAY FROM AREAS OF HIGH FIRE HAZARD & SHOULD BE PERIODICALLY INSPECTED & MONITORED.

Source: Hazardous Substances Data Bank (HSDB)

Reactivity

N,N'-DIPHENYL-P-PHENYLENEDIAMINE may react with oxidizing materials (NTP, 1992). Neutralizes acids in exothermic reactions to form salts plus water. May be incompatible with isocyanates, halogenated organics, peroxides, phenols (acidic), epoxides, anhydrides, and acid halides. Flammable gaseous hydrogen may be generated in combination with strong reducing agents, such as hydrides.

Source: CAMEO Chemicals

Planning storage for a mix of chemicals? Check N,N'-Diphenyl-P-Phenylene… in the storage compatibility matrix →

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