Chemical Properties
White Solid
Uses
A compound that forms synthetic resins with formaldehyde
Definition
ChEBI: A trimer of cyanamide, with a 1,3,5-triazine skeleton.
Uses
Forms synthetic resins with formaldehyde.
General Description
Colorless to white monoclinic crystals or prisms or white powder. Sublimes when gently heated.
Reactivity Profile
MELAMINE(108-78-1) is incompatible with strong oxidizing agents and strong acids . 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.
Air & Water Reactions
Insoluble in water.
Hazard
Toxic by ingestion, skin, and eye irritant.
Questionable carcinogen.
Potential Exposure
Manufactured from urea, melamine
is used in the manufacture of plastics, melamineformaldehyde resins; rubber, synthetic textiles; laminates,
adhesives, and molding compound
Fire Hazard
Literature sources indicate that this compound is nonflammable.
First aid
If this chemical gets into the eyes, remove any
contact lenses at once and irrigate immediately for at least
15 minutes, occasionally lifting upper and lower lids. Seek
medical attention immediately. If this chemical contacts the
skin, remove contaminated clothing and wash immediately
with soap and water. Seek medical attention immediately.
If this chemical has been inhaled, remove from exposure,
begin rescue breathing (using universal precautions, including resuscitation mask) if breathing has stopped and CPR if
heart action has stopped. Transfer promptly to a medical
facility. When this chemical has been swallowed, get medical attention. Give large quantities of water and induce
vomiting. Do not make an unconscious person vomit
Incompatibilities
Incompatible with oxidizers (chlorates,
nitrates, peroxides, permanganates, perchlorates, chlorine,
bromine, fluorine, etc.); contact may cause fires or explosions. Keep away from alkaline materials, strong bases,
strong acids, oxoacids, epoxides. Melamine 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,
nitrides, alkali metals, and sulfides.
Description
Melamine-formaldehyde resin (MFR) is an active
ingredient of strong (reinforced) plasters. Sensitization
was reported in a plaster-room technician, who applied
resin-reinforced pIaster casts, and in dental technicians.
MFR was contained in a strong dental pIaster
used for mouldings. Used as a textile finish res in, it was
also found to be an allergen in a women who replaced
clothes in a store. MFR also releases formaldehyde,
which may be the sensitizer.
Preparation
The standard route to melamine is from urea. Urea is
heated in the presence of ammonia at 250-350??C and 4--20 MPa. The
reaction probably involves the simultaneous dehydration and hydration of
urea to form cyanamide and ammonium carbamate; trimerization of the
cyanamide then leads to melamine:
Thus only 50% of the urea used gives melamine in one step and ammonium
carbamate has to be separated and converted to urea for recycling. Despite
this limitation, the urea route is the most economical of currently available
routes.
Production Methods
Melamine is prepared almost exclusively by the urea
process—the action of ammonia on urea. It is produced
worldwide.
Production Methods
The compound now is synthesized from urea.
Flammability and Explosibility
Nonflammable
Carcinogenicity
A bioassay of melamine was
conducted in rats and mice by NTP. Male F344 rats and
B6C3F1 mice were administered melamine in their diets at
concentrations of 2250 or 4500 ppm daily for 103 weeks.Female rats were fed 4500 or 9000 ppm melamine. At the end
of 111 weeks, surviving animals were killed and examined.
storage
Color Code—Blue: Health Hazard/Poison: Store in a secure poison location. Prior to working with this chemical you should be trained on its proper handling and storage. Store in tightly closed containers in a cool, well-ventilated area away from strong oxidizers and strong acids. Where possible, automatically pump liquid from drums or other storage containers to process containers. A regulated, marked area should be established where this chemical is handled, used, or stored in compliance with OSHA Standard 1910.1045.
Purification Methods
Crystallise Melamine from water or dilute aqueous NaOH. It sublimes at ~240o on prolonged heating. [Beilstein 26 I 74, 26 II 132, 26 III/IV 1253.]
Toxics Screening Level
The initial risk screening level (IRSL) for melamine is 1.5 μg/m3 based on an annual averaging time.
