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

1,3,5-Trioxane

1,3,5-Trioxane is a crystalline solid with a characteristic chloroform-like odor.

CAS 110-88-3 C3H6O3 90.08 g/mol Danger

01 · Identification

What 1,3,5-Trioxane is

1,3,5-Trioxane is a crystalline solid with a characteristic chloroform-like odor. Its molecular formula is C3H6O3 and its molecular weight is 90.08 g/mol. It boils at 115 °C, melts at 64 °C.

Under the GHS it carries the signal word Danger.

CAS number110-88-3
EC number203-812-5
Index number605-002-00-0
Molecular formulaC3H6O3
Molecular weight90.08 g/mol

Other names for 1,3,5-Trioxane

  • 1,3,5-trioxan
  • trioxymethylene

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 1,3,5-Trioxane
CodeHazard statement
H228 Flammable solid.
H361d Suspected of damaging the unborn child.
H335 May cause respiratory irritation.

Precautionary statements: P201, P280, P308, P313

03 · Physical and chemical properties

1,3,5-Trioxane 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 114.5 °C (238.1 °F) at 759 mmHg HSDB
Melting point 64 °C (147.2 °F) HSDB
63.89 °C (147 °F) CAMEO
Density 1.17 g/cm³ at 65 °C HSDB
Solubility SOL IN BENZENE, CARBON TETRACHLORIDE, CHLOROFORM, CARBON DISULFIDE HSDB
greater than or equal to 100 mg/mL at 68 °F (NTP, 1992) at 20 °C CAMEO
Vapor pressure 13 mmHg at 25 °C CAMEO
13 mmHg Haz-Map
Flash point 45 °C (113 °F) HSDB
Autoignition temperature 413.89 °C (777 °F) HSDB
Lower explosive limit (LEL) 3.6 % by volume CAMEO
EXPLOSIVE LIMITS IN AIR 3.5-29%. HSDB
Upper explosive limit (UEL) 28.7 % by volume CAMEO
Vapor density 3.1 (air = 1) CAMEO

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

04 · Source notes

Further notes on 1,3,5-Trioxane

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 WATER: 17.2 G/100 ML @ 18 °C, 21.2 @ 25 °C; EASILY SOL IN ALC, KETONES, ETHER, ACETONE, ORG SOLVENTS, CHLORINATED & AROMATIC HYDROCARBONS; SLIGHTLY SOL IN PENTANE, PETROLEUM ETHER, LOWER PARAFFINS

Source: HSDB

05 · Handling and storage

Storing and handling 1,3,5-Trioxane

Storage conditions

STORE IN COOL, DRY, WELL-VENTILATED PLACE AWAY FROM SOURCES OF HEAT & IGNITION. SEPARATE FROM COMBUSTIBLES, & ACIDIC, ALKALINE, & OXIDIZING MATERIALS. /PARAFORMALDEHYDE/

Source: Hazardous Substances Data Bank (HSDB)

Reactivity

1,3,5-TRIOXANE is stable under normal laboratory conditions but is unstable in the presence of acids, which initiate polymerization. Sublimes readily. May react with oxidizing matter (NTP, 1992). A stable polymeric product of formaldehyde that in the presence of strong aqueous acids will depolymerize (reforming the parent formaldehyde). Inert to strong alkalis. Readily converted in non aqueous solutions to the monomeric formaldehyde by small concentrations of acid---the rate of conversion is directly proportional to the concentration of the acid.

Source: CAMEO Chemicals

Planning storage for a mix of chemicals? Check 1,3,5-Trioxane in the storage compatibility matrix →

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