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

2-phenylpropene

2-phenylpropene is a colorless liquid with a characteristic odor.

CAS 98-83-9 C9H10 118.18 g/mol Warning

01 · Identification

What 2-phenylpropene is

2-phenylpropene is a colorless liquid with a characteristic odor. Its molecular formula is C9H10 and its molecular weight is 118.18 g/mol. It boils at 165 °C, melts at -23.2 °C.

Under the GHS it carries the signal word Warning. It is classed as flammable agents - 2nd degree.

CAS number98-83-9
EC number202-705-0
Index number601-027-00-6
Molecular formulaC9H10
Molecular weight118.18 g/mol
Chemical class Flammable agents - 2nd degree

Other names for 2-phenylpropene

  • α-methylstyrene

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 2-phenylpropene
CodeHazard statement
H226 Flammable liquid and vapour.
H335 May cause respiratory irritation.
H319 Causes serious eye irritation.
H411 Toxic to aquatic life with long lasting effects.

Precautionary statements: P210, P233, P241, P242, P264, P273, P280, P305, P313, P337, P338, P391, P403, P501

03 · Physical and chemical properties

2-phenylpropene 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 165.4 °C (329.7 °F) HSDB
165.56 °C (330 °F) NIOSH
165.39 °C (329.7 °F) at 760 mmHg CAMEO
Melting point -23.2 °C (-9.8 °F) HSDB
-23.33 °C (-10 °F) NIOSH
-22.78 °C (-9 °F) CAMEO
Density 0.9106 g/cm³ HSDB
0.91 g/cm³ NIOSH
0.91 g/cm³ at 20 °C CAMEO
Solubility SOL IN ALC; SOL IN ALL PROPORTIONS IN ACETONE, CARBON TETRACHLORIDE HSDB
Sol in benzene, chloroform HSDB
Sol in ether HSDB
Vapor pressure 2 mmHg NIOSH
1.9 mmHg at 20 °C CAMEO
1.9 mmHg at 25 °C HSDB
Flash point 83.89 °C (183 °F) CLOSED CUP HSDB
57.8 °C (136 °F) Cleveland open-cup HSDB
53.89 °C (129 °F) NIOSH
Autoignition temperature 574.44 °C (1066 °F) HSDB
574 °C (1065.2 °F) ICSC
Lower explosive limit (LEL) 6.1 % by volume upper flammable limit HSDB
6.1 % by volume upper HSDB
3.4 % by volume upper HSDB
Upper explosive limit (UEL) 6.1 % by volume NIOSH
6.6 % by volume ICSC
Vapor density 4.08 (air = 1) CAMEO
Odor threshold Odor detection in air, 5.20X10-2 ppm (purity not specified) HSDB
Odor recognition in air, 1.60X10-1 ppm (purity not specified) HSDB
Odor (low) 0.2496 mg/cu m; Odor (high) 960.0 mg/cu m; Irritating concn 960.0 mg/cu m. HSDB
Critical temperature and pressure 384 °C (723.2 °F) HSDB

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

04 · Handling and storage

Storing and handling 2-phenylpropene

Storage conditions

DURING STORAGE IT IS FREQUENTLY STABILIZED WITH TERT-BUTYL CATECHOL AS INHIBITOR.

Source: Hazardous Substances Data Bank (HSDB)

Incompatible materials

Oxidizers, peroxides, halogens, catalysts for vinyl or ionic polymers; aluminum, iron chloride, copper [Note: Usually contains an inhibitor such as tert-butyl catechol].

Source: Hazardous Substances Data Bank (HSDB)

Reactivity

ISOPROPENYLBENZENE is easily peroxidizable; the peroxide may initiate exothermic polymerization of the bulk material. Reacts violently with strong oxidizing agents [Handling Chemicals Safely, 1980 p. 866; Bretherick, 1979 p. 160].

Source: CAMEO Chemicals

Planning storage for a mix of chemicals? Check 2-phenylpropene in the storage compatibility matrix →

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