1.4- Benzenedicarboxylate acid

The carboxylic acid produced m the greatest amounts is 1 4 benzenedicarboxylic acid (terephthahc acid) About 5 X 10 Ib/year is produced m the United States as a starting material for the preparation of polyester fibers One important process converts p xylene to terephthahc acid by oxidation with nitric acid... 

Aromatic polyamide (aramid) membranes are a copolymer of 1-3 diaminobenzene with 1-3 and 1-4 benzenedicarboxylic acid chlorides. They are usually made into fine hollow fibers, 93 [Lm outer diameter by 43 [Lm inner diameter. Some flat sheet is made for spirals. These membranes are widely used for seawater desalination and to some extent for other process applications. The hollow fibers are capable of veiy high-pressure operation and have considerably greater hydrolytic resistance than does CA. Their packing density in hoUow-fiber form makes them veiy susceptible to colloidal fouling (a permeator 8 inches in diameter contains 3 M fibers), and they have essentially no resistance to chlorine. 

Kevlar, a nylon polymer prepared by reaction of 1,4-benzenedicarboxylic acid (terephthalicacid) with 1,4-benzenediamine (p-phenyienediamine), is so strong that it s used to make bulletproof vests. Draw the structure of a segment of Kevlar. 

The predominant RO membranes used in water applications include cellulose polymers, thin film oomposites (TFCs) consisting of aromatic polyamides, and crosslinked polyetherurea. Cellulosic membranes are formed by immersion casting of 30 to 40 percent polymer lacquers on a web immersed in water. These lacquers include cellulose acetate, triacetate, and acetate-butyrate. TFCs are formed by interfacial polymerization that involves coating a microporous membrane substrate with an aqueous prepolymer solution and immersing in a water-immiscible solvent containing a reactant [Petersen, J. Memhr. Sol., 83, 81 (1993)]. The Dow FilmTec FT-30 membrane developed by Cadotte uses 1-3 diaminobenzene prepolymer crosslinked with 1-3 and 1-4 benzenedicarboxylic acid chlorides. These membranes have NaCl retention and water permeability claims. 

Introduction. The production of terephthalic acid (1,4-benzenedicarboxylic acid) has several interesting features. First, it is one of the examples of a homogeneous, radical-catalysed oxidation with the use of dioxygen and cobalt salt initiators. Secondly, it is an example of a catalyst/product separation involving a filtration of the product from the liquid that contains the catalyst. Crystallisation on such a huge scale is not very attractive, but the low solubility of phthalic acid in many solvents and the high boiling point do not allow any other solution. Theoretically, a solvent-solvent extraction would be an option, but we are not aware of a viable combination of solvents. 

Preparation 211.—Dimethyl Terephthalate (Dimethyl ester of 1 4-benzenedicarboxylic acid). 

Just as diacids and diamines react to give polyamides, diacids and dialcohols react to give polyesters. The most industrially important polyester, made from reaction of terephthalic acid (1,4-benzenedicarboxylic acid) with ethylene glycol (1,2-ethanediol), is used under the trade name Dacron to make clothing fiber and under the name Mylar to make plastic film and recording tape. 

Propiolic acid 2-Propynoic acid Terephdialic acid 1,4-Benzenedicarboxylic acid... 

Among polyesters synthesized from 1,4-benzenedicarboxylic acid and aliphatic diols, poly (ethylene terephthalate) (PET) and poly (butylene terephthalate) (PBT) are the most frequently applied ones. Hydrolysis is evidently the easiest chemical recycling technique of polyesters, however they may be mixed with other waste plastics, thus it is useful to know the properties of their pyrolysis product. 

It is prepared by reaction of ethylene glycol with 1,4-benzenedicarboxylic acid (tcre-phthalic acid). Draw the structure of PET. ... 

C16H2204 1,4-benzenedicarboxylic acid, dibutyl ester 1962-75-0 550 48 48.755 2 29697 C16H31I trans-1 -iodo-1 -hexadecene 66271-74-7 618.15 55.344 1,2... 

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