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

P-Phenylenediamine

P-Phenylenediamine is white to slightly red crystals.

CAS 106-50-3 C6H8N2 108.14 g/mol Danger

01 · Identification

What P-Phenylenediamine is

P-Phenylenediamine is white to slightly red crystals. Its molecular formula is C6H8N2 and its molecular weight is 108.14 g/mol. It boils at 267 °C, melts at 146 °C.

Under the GHS it carries the signal word Danger. It is classed as hazardous Air Pollutants (HAPs).

CAS number106-50-3
EC number203-404-7
Index number612-028-00-6
Molecular formulaC6H8N2
Molecular weight108.14 g/mol
Chemical class Hazardous Air Pollutants (HAPs)

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 P-Phenylenediamine
CodeHazard statement
H331 Toxic if inhaled.
H311 Toxic in contact with skin.
H301 Toxic if swallowed.
H319 Causes serious eye irritation.
H317 May cause an allergic skin reaction.
H400 Very toxic to aquatic life.
H410 Very toxic to aquatic life with long lasting effects.

Precautionary statements: P260, P261, P264, P270, P271, P272, P273, P280, P301, P302, P304, P305, P310, P313, P330, P333, P337, P338, P352, P391, P501

03 · Physical and chemical properties

P-Phenylenediamine 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 267 °C (512.6 °F) HSDB
267.22 °C (513 °F) NIOSH
267.22 °C (513 °F) at 760 mmHg CAMEO
Melting point 146.11 °C (295 °F) NIOSH
140 °C (284 °F) CAMEO
Density 1.1 g/cm³ ICSC
1 g/cm³ DOE PAC
Greater than 1 (water= 1) HSDB
Solubility SOL IN 100 PARTS COLD WATER; SOL IN ALCOHOL, CHLOROFORM, ETHER HSDB
SOL IN HOT BENZENE HSDB
Water solubility= 38,000 ppm HSDB
Vapor pressure 1 mmHg below this value NIOSH
1 mmHg below this value, at 21 °C, technical product HSDB
Flash point 155.56 °C (312 °F) NIOSH
155 °C (311 °F) CAMEO
156 °C (312.8 °F) ICSC
Autoignition temperature 400 °C (752 °F) ICSC
Lower explosive limit (LEL) Minimum explosive concentration: 0.025 g/l HSDB
The finely powdered base is a significant dust explosion hazard. HSDB
Combustible Solid NIOSH
Vapor density 3.72 (air = 1) HSDB
3.7 (air = 1) ICSC

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

04 · Handling and storage

Storing and handling P-Phenylenediamine

Storage conditions

Keep well closed and protected from light.

Source: Hazardous Substances Data Bank (HSDB)

Incompatible materials

Contact with strong oxidizers may cause fires and explosions.

Source: Hazardous Substances Data Bank (HSDB)

Reactivity

P-PHENYLENEDIAMINE is the stongest of the weak aromatic bases. It neutralizes acids in weak exothermic reactions to form salts. May be incompatible with isocyanates, halogenated organics, peroxides, phenols (acidic), epoxides, anhydrides, and acid halides. Reacts readily with oxidizing agents (NTP, 1992).

Source: CAMEO Chemicals

Planning storage for a mix of chemicals? Check P-Phenylenediamine in the storage compatibility matrix →

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