Phthalic acids terephthalic acid

AMINOHEPTANE ISOPHTHALOYL CHLORIDE PHTHALIC ANHYDRIDE ETHYNYLBENZENE ISOPHTHALIC ACID PHTHALIC ACID TEREPHTHALIC ACID BENZOTHIOPHENE INDOLE... 

An example of two ion exchange separations are shown in Figure 5-32. The first separation is of phthalic acid, terephthalic acid and isophthalic acid using a 10-mM boric acid mobile phase adjusted to pH 9.2 using sodium hydroxide. The other separation in Figure 5-32 is of caffeine, w-acetyl-p-aminophenyl, aspirin, and salicylamide. In order for all of these compounds to be eluted in a reasonable time, the 10-mM boric acid solution also contains 20 mM sodium nitrate for ionic strength adjustment. 

Glycidyl Esters. Glycidyl ester resins were originally developed for electrical applications. Glycidyl esters of phthalic acid, hexahydro phthalic acid, terephthalic acid or trimellitic acid (e.g. Araldite PY 284, PT 910) cured with carboxy functional polyesters or polyacrylates at elevated temperatures give coating with both excellent colour stability and outdoor resistance. 

Isophthalic acid Phthalic acid Terephthalic acid C8H6O4 K Potassium biphthalate C8H6O7S... 

Consider, for example, six different pairs of analytes, all containing an aromatic ring (bases, acids, isomers, etc.) which were separated under different conditions (methanol, methanol/water, mefhanol/buffer). The more symmetrical the hexagon, the more applicable is the corresponding stationary phase for the separation of aromatic substances in general. In addition, it is easy to decide which column is suitable, e.g., for the separation of quite strong aromatic acids (phthalic acid/terephthalic acid, Tere/Phthal ), which is best for weaker aromatic acids (3-hydroxy-/4 hydroxybenzoic acid, 3/4-OH ), and which is best for planar/nonplanar aromatic substances (triphenylene/o-terphenyl, Triph/ o-Ter ). 

Detection and result The chromatogram was freed from mobile phase and immersed for 3 s in the dipping solution and heated to 125°C for 5 — 10 min. The carboxylic acids terephthalic acid (tiRi 5), succinic acid (fiRi 50 — 55), phthalic acid (hRf 55 — 60), suberic acid (tiRi 60 — 65), sebacic acid (fiRi 65 — 70), benzoic acid (tiRi 75 — 80) and salicylic acid (hRf 80 — 85) yielded brown zones on a light brown background. The detection limit was 2 pg acid per chromatogram zone. 

Oleochemical based dicarboxylic acids - azelaic, sebacic, and dimer acid (Figs. 4.5 and 4.6) - amount to ca. 100000 tonnes year-1 as components for polymers. This is about 0.5% of the total dicarboxylic acid market for this application, where phthalic and terephthalic acids represent 87%. The chemical nature of these oleochemical derived dicarboxylic acids can alter or modify condensation polymers, and, used as a co-monomer, will remain a special niche market area. Some of these special properties are elasticity, flexibility, high impact strength, hydrolytic... 

Manufacture of TNT, aviation gasoline, solvent Solvent, manufacture of aviation gasoline Phthalic anhydride Terephthalic acid (for plastics)... 

Phthalic anhydride Terephthalic acid (MTA) Terephthalic acit (PTA) Lyondell Chemical Isooctane... 

Nitro-p-phthalic Acid (Nitroterephthalic Acid). Only one isomer is possible. Crysts, mp 268— 70°. Easily sol in ale or eth, sol in hot w. Can be prepd by nitration of terephthalic acid or by other methods given in the Refs. Some of its salts are probably expl... 

Benzenedicarboxylic acids have trivial names. Benzene-1,4-dicarboxylic acid (terephthalic acid, 3) is used in the manufacture of commercially important polyesters. Esters of benzene-1,2-dicarboxylic acid (phthalic acid) are used for plasticizing polymers. 

Unsaturated polyesters are made commercially by condensing maleic anhydride, phthalic anhydride, terephthalic acid or HEX acid with ethylene glycol, 1,2-propylene glycol, neopentyl glycol, oxyethylated bisphenols, or cyclododecane diol, e.g.. 

Figure 3.12 Gas chromatograms of hydrolysates of (a) silyl derivative of polyethylene terephthalate, (b) silyl derivative of ethylene glycol 1,4 butane diol and trans isomers of 1,4 cyclohexane diol dimethanol and (c) silyl derivative of iso- phthalic and terephthalic acids derived from a polyester. Reproduced with permission from B.J. Allen, G.M. Elser, K.P. Keller and H.D. Kinder, Analytical Chemistry, 1977, 49, 741. 1977, ACS...

The multi-stage processes include those in the synthesis of adipinic acid, which is required for nylon manufacture, the production of synthetic detergents—alkylaryl sulphonate, and the synthesis of the dimethyl ester of tere-phthalic acid (terephthalate), that is required for the processing of terylene fibre. The last example will include a description of the system (2.3) according to components by means of system (2.7). 

Although phthalic anhydride is the most common dibasic acid for producing alkyd resins, isophthalic acid, terephthalic acid, trimellitic anhydride and maleic anhydride are also used. Isophthalic and terephthalic acid are often used in exterior coatings where improved hydrolitic stability is required. Maleic anhydride is used with other polybasic acids as a modifier to increase viscosity and film hardness. Trimellitic anhydride is used in making water soluble alkyds for specific applications. 

See also Terephthalic acid.) pHTHALIC ACID AND OTHERBENZENEPOLYCARBOXYLIC ACIDS] (Vol 18)... 

Reactions of the Methyl Groups. These reactions include oxidation, polycondensation, and ammoxidation. PX can be oxidized to both terephthahc acid and dimethyl terephthalate, which ate then condensed with ethylene glycol to form polyesters. Oxidation of OX yields phthaUc anhydride, which is used in the production of esters. These ate used as plasticizers for synthetic polymers. MX is oxidized to isophthaUc acid, which is also converted to esters and eventually used in plasticizers and resins (see Phthalic acids and otherbenzenepolycarboxylic acids). 

The present method for preparing aromatic dicarboxylic acids has been used to convert phthalic or isophthalic acid to tereph-thalic acid (90-95%) 2,2 -biphenyldicarboxylic acid to 4,4 -biphenyldicarboxylic acid 3,4-pyrroledicarboxylic acid to 2,5-pyr-roledicarboxylic acid and 2,3-pyridinedicarboxylic acid to 2,5-pyridinedicarboxylic acid. A closely related method for preparing aromatic dicarboxylic acids is the thermal disproportionation of the potassium salt of an aromatic monocarboxylic acid to an equimolar mixture of the corresponding aromatic hydrocarbon and the dipotassium salt of an aromatic dicarboxylic acid. The disproportionation method has been used to convert benzoic acid to terephthalic acid (90-95%) pyridine-carboxylic acids to 2,5-pyridinedicarboxylic acid (30-50%) 2-furoic acid to 2,5-furandicarboxylic acid 2-thiophenecar-boxylic acid to 2,5-thiophenedicarboxylic acid and 2-quinoline-carboxylic acid to 2,4-quinolinedicarboxylic acid. One or the other of these two methods is often the best way to make otherwise inaccessible aromatic dicarboxylic acids. The two methods were recently reviewed. ... 

The phthalic acid and benzoic acid are reacted to form a reaction intermediate. The reaction intermediate is dissolved in sulfuric acid, which precipitates terephthalic acid (TPA). Fifty percent of the TPA is sold as a product and 50 percent is further processed at your facility into polyester fiber. The TPA Is treated with ethylene glycol to form an intermediate product, which is condensed to polyester. 

Hajek et al. [173] have reported a detailed kinetic study of the solid phase decomposition of the ammonium salts of terephthalic and iso-phthalic acids in an inert-gas fluidized bed (373—473 K). Simultaneous release of both NH3 molecules occurred in the diammonium salts, without dehydration or amide formation. Reactant crystallites maintained their external shape and size during decomposition, the rate obeying the contracting volume equation [eqn. (7), n = 3]. For reaction at 423 K of material having particle sizes 0.25—0.40 mm, the rate coefficients for decompositions of diammonium terephthalate, monoammonium tere-phthalate and diammonium isophthalate were in the ratio 7.4 1.0 134 and values of E (in the same sequence) were 87,108 and 99 kJ mole-1. 

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