Фталық ангидрид: қасиеттері, қолданылуы және денсаулыққа әсері

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| Verifiedfields = changed
| Watchedfields = changed
| verifiedrevid = 486601904
| Name = Phthalic anhydride
| ImageFileL1 Ref =
| ImageFileL1 = Phthalic anhydride 2D Skeletal. png
| ImageNameL1 = Skeletal formula of phthalic anhydride
| ImageFileR1 = Phthalic anhydride 3D spacefill. png
| ImageNameR1 = Space filing model
| ImageFile2 = Sample of phthalic anhydride. jpg
| PIN = 2 Benzofuran 1,3 dione
| OtherNames = Isobenzofuran 1,3 dione
| ExploLimits = 1.7%–10.5%
| IDLH = 60 mg/m3
| REL = TWA 6 mg/m3 (1 ppm) The modern industrial variant process instead uses vanadium pentoxide (V2O5) as the catalyst in a gas phase reaction with naphthalene using molecular oxygen.]] Phthalic anhydride can also be prepared from phthalic acid by simple thermal dehydration above 210°C.

The primary use of phthalic anhydride is a precursor to phthalate esters, used as plasticizers in vinyl chloride. Phthalate esters are derived from phthalic anhydride by the alcoholysis reaction. Phenolphthalein can be synthesized by the condensation of phthalic anhydride with two equivalents of phenol under acidic conditions (hence the name). It was discovered in 1871 by Adolf von Baeyer.

Phthalic anhydride treated with cellulose acetate gives cellulose acetate phthalate (CAP), a common enteric coating excipient that has also been shown to have antiviral activity. Phthalic anhydride is a degradation product of CAP.

Phthalic anhydride is a versatile intermediate in organic chemistry, in part because it is bifunctional and cheaply available.

Phthalic anhydride is used to dehydrate short chain nitro alcohols to yield nitroalkenes, compounds with a high tendency to polymerize.

The most probable human exposure to phthalic anhydride is through skin contact or inhalation during manufacture or use. Studies show that exposure to phthalic anhydride can cause rhinitis, chronic bronchitis, and asthma. Phthalic anhydride's reaction on human health is generally an asthma–rhinitis–conjunctivitis syndrome or a delayed reaction and influenza like symptoms and with increased immunoglobulin (E and G) levels in the blood.