Chemical Properties
Trimellitic anhydride is a white powder or flakes. It is the anhydride of trimellitic acid (1,2,4-benzenetricarboxylic acid). It is soluble in water, ethanol, acetone and other general organic solvents.
Uses
Trimellitic Anhydride is mainly used as raw material for polyester resin,polyimide resin,plasticizer TOTM ,and also be used for producing heatproof & insulating,adhesive,surfactant, paint,synthesize dye materials etc.
Trimellitic anhydride is used as an embossing agent for vinyl flooring and as a curing agent for epoxy resins. It is also used as an intermediate for the synthesis of surface coatings chemicals, adhesives, polymers, dyes printing inks, pharmaceuticals .
Uses
Trimellitic anhydride is mainly applied to produce good heat-proof, weather-proof and solvent-proof trimellitate plasticizers, among which the most popular product is tri(2-ethylhexyl)trimellitate. It is also used to synthesize polyester resins.TMA can also be applied to curing agent of epoxy resins.
Definition
ChEBI: Trimellitic anhydride is a 2-benzofuran compound having oxo groups at the 1- and 3-positions and a carboxy substituent at the 5-position; the cyclic anhydride formed from the carboxy groups at the 1- and 2-positions of trimellitic acid. It has a role as an epitope, an allergen and a hapten. It is a cyclic dicarboxylic anhydride, a dioxo monocarboxylic acid and a member of 2-benzofurans. It is functionally related to a phthalic anhydride and a trimellitic acid.
General Description
1,2,4-Benzenetricarboxylic anhydride(TA) is a hydrophilic monomer with multipurpose usage; as a curing agent for epoxy based resins and as a plasticizer for polyvinyl chloride(PVC).
Air & Water Reactions
Sensitive to moisture. Hydrolyzes slowly. Solutions in water or alcohol may be unstable. Insoluble in water.
Reactivity Profile
1,2,4-Benzenetricarboxylic anhydride reacts exothermically with water. This reaction is expected to be slow, but can become vigorous if local heating accelerates it. Reaction with water is accelerated by acids. Incompatible with acids, strong oxidizing agents, alcohols, amines, and bases. Incompatible with strong oxidizing agents, strong acids or strong bases. .
Hazard
Toxic by inhalation. Respiratory sensitization.
Health Hazard
Trimellitic anhydride (TMAN)
causes both respiratory irritation and immunologic
respiratory disease.
Safety Profile
Moderately toxic by
ingestion. Has caused pulmonary edema
from inhalation. Irritant to lungs and air
passages. May be a powerful allergen.
Typical attack consists of breathlessness,
wheezing, cough, running nose,
immunologcal sensitization, and asthma
symptoms. When heated to decomposition
it emits acrid smoke and irritating fumes.
See also ANHYDRIDES.
Synthesis
3-Xylene is carbonylated with carbon monoxide in the presence of boron trifluoride and hydrogen fluoride to form 2,4-dimethylbenzaldehyde. 2,4-Dimethylbenzaldehyde is decomplexed from the acids, purified, and oxidized to trimellitic acid. Trimellitic acid is subjected to normal dehydration and purification steps to obtain high quality trimellitic anhydride.
Potential Exposure
TMA is used to produce trimellitate
plasticizers, poly (amide-imide) polymers; in paints, enamels,
and coatings; polymers, polyesters; as a curing agent for
epoxy and other resins; in vinyl plasticizers; agricultural chemicals;
dyes and pigments; pharmaceuticals, surface active
agents; modifiers, intermediates, and specialty chemicals.
Carcinogenicity
There are no reports of carcinogenicity
associated with TMAN exposure. It was not
mutagenic in bacterial assays with or without
metabolic activation. No teratogenic effects
or developmental toxicity was seen in rats
or guinea pigs exposed to 500mg/m3 for
6 hours/day during their period of major
organogenesis.
Incompatibilities
Dust can cause an explosion.
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. Reacts slowly with water, forming trimellitic
acid. Compounds of the carboxyl group react with all
bases, both inorganic and organic (i.e., amines) releasing
substantial heat, water and a salt that may be harmful.
Waste Disposal
Dissolve or mix the material
with a combustible solvent and burn in a chemical incinerator
equipped with an afterburner and scrubber. All federal,
state, and local environmental regulations must be
observed.
