|Chemical Abstract Number (CAS #)||
|Synonyms||Phthalic anhydride||1,3-Isobenzofurandione||1,2-Benzenedicarboxylic acid anhydride
Link to the National Library of Medicine's Hazardous Substances
Database for more details
on this compound.
|Use|| MFR PHTHALEINS, PHTHALATES, BENZOIC ACID, SYNTHETIC INDIGO,
ARTIFICIAL RESINS (GLYPTAL).
CHEM INT FOR DIOCTYL PHTHALATES-EG, DI(2-ETHYLHEXYL), OTHER
PHTHALATE PLASTICIZERS-EG, DIBUTYL, INSECT REPELLENTS-EG, DIMETHYL
PHTHALATE, UNSATURATED POLYESTER RESINS, ALKYD RESINS, DYES AND
PIGMENTS, ISATOIC ANHYDRIDE, HALOGENATED PHTHALIC ANHYDRIDES,
DIALLYL PHTHALATE, URETHANE POLYESTER POLYOLS, PHENOLPHTHALEIN;
CURING AGENT FOR EPOXY RESINS.
Scorch inhibitor for rubber stocks.
Alkyd resins, plasticizers, hardener for resins, polyesters, synthesis of phenolphthalein and other
phthaleins, many other dyes, chlorinated products, pharmaceutical intermediates, insecticides,
diethyl phthalate, dimethyl phthalate, laboratory reagent.
FORMERLY IT WAS USED IN THE SYNTHESIS OF ALIZARINE, XANTHENE,
ANTHRAQUINONE & RHODAMINE.
|Consumption Patterns|| CHEM INT FOR: PHTHALATE PLACTICIZERS, 53%; UNSATURATED
POLYESTER RESINS, 22%; ALKYD RESINS, 19%; OTHER USES (EG, CHEM INT FOR
DYES, RUBBER RETARDER), 6% (1983)
End use pattern: phthalate plasticizers, 50%; unsaturated polyesters, 25%; alkyd resins, 15%;
miscellaneous, 10% (1985)
CHEMICAL PROFILE: Phthalic Anhydride. Plasticizers, 48%; polyester resins, 23%; alkyd
resins, 19%; miscellaneous, 5%; exports, 5%.
CHEMICAL PROFILE: Phthalic anhydride. Demand: 1988: 1,050 million lb; 1989: 950 million
lb; 1993 projected/: 1,190 million lb. (Includes exports, but not imports, which totaled 30 million
lb last year.)
TODAY 60% OF PRODUCTION IS USED AS A PLASTICIZER IN VINYL CHLORIDE
POLYMERIZATION. ABOUT 30% OF OUTPUT IS USED FOR THE PRODUCTION OF
SATURATED & UNSATURATED POLYESTER RESINS, FOR PESTICIDES & AS
CONSTITUENTS OF CERTAIN ESSENCES & PERFUMES. THE REMAINING 10% IS
EMPLOYED IN THE PRODUCTION OF ALKYD RESINS USED IN PAINTS &
LACQUERS, OF PHTHALOCYANINE DYES & ALSO FOR THE PREPARATION OF
|Apparent Color|| WHITE, LUSTROUS NEEDLES; Colorless or pale yellow solid flakes; Colorless
needles; monoclinic or rhombic prisms; White needles from alcohol & benzene
|Odor|| MILD; Characteristic choking odor, acrid
|Boiling Point|| 295 DEG C
|Melting Point|| 130.8 DEG C
|Molecular Weight|| 148.11
|Density|| 1.20 @ 135 deg C (liquid), 1.53 @ 20 deg C (solid)
|Odor Threshold Concentration|| Air: 0.053 ul/l; odor safety class C; C= Less than 50% of distracted persons perceive
warning of TLV.
0.32-0.72 mg/cu m
|Sensitivity Data|| DUST VAPOR OR FUMES ARE IRRITATING TO EYES .
|Environmental Impact|| Phthalic anhydride release to the atmosphere could result from its manufacture and use
in many products and its use in the manufacture of other commercial materials, polyester resins,
and alkyd resins, phthaleins, phthalates, benzoic acid, sythetic indigo, artifical resins (glyptal),
synthetic fibers, dyes, pigments, pharmaceuticals, insecticides and chlorinated products. It is
released from industrial plants which produce phthalic anhydride by oxidation of xylenes and
naphthalene; from the incineration of industrial refuse and water sludges and slurries from plastic
products and other manufacturing processes; phthalic anhydride has been detected in leachate
from municipal and separate industrial wastes containing plastics. If phthalic anhydride is released
to soil, it will not be expected to sorb to the soil. It is expected to hydrolyze in moist soils. If it is
released to water it will not be expected to bioconcentrate in aquatic organisms, sorb to
sediments, or to evaporate. Hydrolysis will be a major fate process based on an estimated half-life
of 1.5 minutes. If it is released to the atmosphere it may be susceptible to direct photolysis. The
estimated vapor-phase half-life in the atmosphere is about 32 days as a result of ring addition of
photochemically produced hydroxyl radicals. Exposure to phthalic anhydride result mainly from
occupational exposure involving the inhalation of contaminated air.
|Environmental Fate|| TERRESTRIAL FATE: If phthalic anhydride is released to soil it will not be expected to
sorb to the soil. Phthalic anhdyride is expected to hydrolyze in moist soils which will prevent its
leaching to the groundwater.
AQUATIC FATE: If phthalic anhydride is released to water it will not be expected to
biconcentrate in aquatic organisms, sorb to sediments, or evaporate. Hydrolysis will be a major
fate process based on an estimated half-life of approximately 1.5 minutes calculated using a
reported observed rate constant of 7.9X10-3/sec for hydrolysis in aqueous solution at 25 deg
C . Phthalic anhydride absorbs light >290 nm and therefore may be susceptible to direct
ATMOSPHERIC FATE: If phthalic anhydride is released to the atmosphere it may be
susceptible to direct photolysis since it absorbs light >290 nm. The estimated vapor-phase half-life
in the atmosphere is about 32 days as a result of addition of photochemically produced hydroxyl
|Drinking Water Impact|| DRINKING WATER: Identified, not quantified in 1 of 14 treated waters, included
treated water from rivers, reservoirs, and groundwater (positive sample was a treated
groundwater after distribution; phthalic anhydride was not reported present in the sources treated
groundwater) . Identified, not quantified in drinking water in the US and in unidentified
drinking water . Identified, not quantified, in drinking water concentrates . US, 10 sites, 10%
pos, identified, not quantified (only pos, Cincinnati, OH) .
EFFL: Identified, not quantified, in advanced waste treatment concentrates . Identified
industrial point sources include industrial plants which oxidize xylenes and naphthalene for
phthalic anhydride production; gross estimate of discharge 5,000 tons/yr; waste treatment and
disposal sources: incineration of industrial refuse and water sludges and slurries from plastic
products adn other manufacturing processes; leaches from municipal and industrial wastes
containing plastics . Identified, not quantified, in effluents from two unspecified chemical