phthalic acid

n. The colorless crystalline ortho-isomer of benzene dicarboxylic acid, C₈H₆O₂, used in the synthesis of dyes, perfumes, and other organic compounds.

phthalic acid

(ˈθælɪk; ˈfθæl-) n (Elements & Compounds) a soluble colourless crystalline acid used in the synthesis of dyes and perfumes; 1,2-benzenedicarboxylic acid. Formula: C6H4(COOH)2[C19 phthalic, from phthal- (see phthalein) +-ic]

phthal′ic ac′id

n. any of three colorless, crystalline, isomeric acids having the formula C₈H₆O₄, used chiefly in the manufacture of dyes, medicine, and perfume. [1855–60]

Thesaurus

Noun

phthalic acid - a colorless acid used to make dyes and perfumesacid - any of various water-soluble compounds having a sour taste and capable of turning litmus red and reacting with a base to form a salt

Translations

Phthalic Acid

phthalic acid

[′thal·ik ′as·əd] (organic chemistry) C₆H₄(CO₂H)₂ Any of three isomeric benzene dicarboxylic acids; the ortho form is usually called phthalic acid, comprises alcohol-soluble, colorless crystals decomposing at 191°C, slightly soluble in water and ether, is used to make dyes, medicine, and synthetic perfumes, and as a chemical intermediate, and is also known as benzene orthodicarboxylic acid; the para form, known as terephthalic acid, is used to make polyester resins (Dacron) and as poultry feed additives; the meta form is isophthalic acid.

Phthalic Acid

(benzenedicarboxylic acid), C₆H₄(COOH)₂, any one of three dicarboxylic acids of the aromatic series: ortho-phthalic acid (or simply phthalic acid), meta-phthalic acid (or isophthalic acid), and para-phthalic acid (or terephthalic acid). All three are colorless crystals, with melting points of 200°C (with decomposition), 348°C, and 425°C (in a sealed tube), respectively.

ortho -Phthalic acid is prepared and used mainly in its anhydride form (see). Of practical importance are the esters of ortho-phthalic acid C₆H₄(COOR)₂, which are liquids with high boiling points; they are used as plasticizers for polyvinyl chloride, polystyrene, and many other polymers (for example, dibutyl phthalate and dioctyl phthalate) and serve as manometric liquids and insect repellents, such as dimethyl phthalate. The dinitrile of ortho-phthalic acid (phthalonitrile) is used in the production of phthalocyanine dyes and polyphthalocyanines. Also of practical importance are the cyclic imide (phthalimide) and dichloranhydride (phthalyl chloride) of ortho-phthalic acid, as well as phthalylsulfathiazole (Ftalazol). Polyester resins based on ortho-phthalic acid and polyhydric alcohols, such as glycerin and pentaerythritol, are widely used; these are called glyptal and penta resins, respectively.

meta-Phthalic acid and para-phthalic acid are prepared by the oxidation of meta-xylene and para-xylene, respectively. They serve as the basis for the commercial production of aromatic polyamides, such as poly-m-phenyleneisophthalamide, and in the production of polyarylates. The interaction of para-phthalic acid or its dimethyl ester with ethylene glycol yields polyethylene terephthalate, which is used in the manufacture of polyester fibers.

V. N. FROSIN

phthalic acid

phthalic acid

phthalic acid

phthal′ic ac′id

Phthalic Acid

phthalic acid

Phthalic Acid

phthalic acid

phthal·ic ac·id

phthalic acid

Words related to phthalic acid

noun a colorless acid used to make dyes and perfumes

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