Polyester fibers terephthalate

The Textile Eiber Product Identification Act (TEPIA) requires that the fiber content of textile articles be labeled (16). The Eederal Trade Commission estabhshed and periodically refines the generic fiber definitions. The current definition for a polyester fiber is "A manufactured fiber ia which the fiber-forming substance is any long-chain synthetic polymer composed of at least 85% by weight of an ester of a substituted aromatic carboxyUc acid, including but not restricted to terephthalate units, and para substituted hydroxyben2oate units."... 

Polyester Fibers Containing Phosphorus. Numerous patents describe poly(ethylene terephthalate) (PET) flame-retarded with phosphoms-containing diftmctional reactants. At least two of these appear to be commercial. 

Some time earlier, Eastman-Kodak has been working on a novel polyester as an entry into the important polyester fiber market and had devised a new ahcychc diol, 1,4-cydohexanedimethanol [105-08-5] effectively made by exhaustive hydrogenation of dimethyl terephthalate. Reaction of the new diol with dimethyl terephthalate gave a crystalline polyester with a higher melting point than PET and it was introduced in the United States in 1954 as a new polyester fiber under the trade name Kodel (5). Much later the same polyester, now called PCT, and a cyclohexanedimethanol—terephthalate/isophthalate copolymer were introduced as mol ding resins and thermoforming materials (6). More recentiy stiU, copolymers of PET with CHDM units have been introduced for blow molded bottie resins (7). 

Polyester fibers are based on poly(ethylene terephthalate) (PET) some modified versions are formed by copolymerization, eg, basic dyeable polyester. The modified forms dye in analogous manner to other fibers of similar charge. 

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. 

Paraxylene is used to make terephthalic acid, the raw material for manufacturing polyester fibers, such as Dacron, Kodel, Fortrel and Terylene. 

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

Polyesters are the most important class of synthetic fibers. In general, polyesters are produced by an esterification reaction of a diol and a diacid. Carothers (1930) was the first to try to synthesize a polyester fiber by reacting an aliphatic diacid with a diol. The polymers were not suitable because of their low melting points. However, he was successful in preparing the first synthetic fiber (nylon 66). In 1946, Whinfield and Dickson prepared the first polyester polymer by using terephthalic acid (an aromatic diacid) and ethylene glycol. 

A similar oxidation is employed industrially for the preparation of the terephthalic acid used in the production of polyester fibers. Approximately 5 million tons per year of p-xylene are oxidized, using air as the oxidant and Co(lll) salts as catalyst. 

TABLE 2.12 Physical Properties of Poly(ethylene terephthalate) (PET) and Polyethylene 2,6-naphthalate) (PEN) Polyester Fibers... 

The most common polyester fiber is polyethylene terephthalate (PET), prepared from ethylene glycol and terephthalic acid. Acrylics... 

In analogy to the transesterification of diethyl terephthalate used in the preparation of commercially important polyester fibers such as Dacron (24), a transesterification reaction waus successfully employed for the preparation of poly(N-acylhydroxyproline esters) (Scheme 1). 

C13-0057. Kodel is a polyester fiber made from terephthalic acid and cyclohexanedimethanol. Draw a segment of Kodel that contains at least four repeat units. 

When the new product to be manufactured is the same as what it started as, for example a new bottle made from bottle scrap, the recycling is referred to as closed-loop. When the new application is different from the starting one, the process is referred to as open-loop recycling, as is the case when the polyethylene terephthalate bottle is used to produce polyester fiber for carpeting. 

PBT resin has been reviewed in many articles, often as part of a larger review of polyesters [1-3], A recent article provides an historic account of polyester development as an alternative to nylon fibers [4], while the review of Kirsch and Williams in 1994 gives a business perspective on polyesters [5], However, an understanding of PBT in the context of the more common polyester polyethylene terephthalate) (PET) is often overlooked. PET dominates the large volume arenas... 

This article is an overview of the novel technology of self-reinforced LCPs with polyesters, poly(ethylene terephthalate) (PET) and poly(ethylene naphtha-late) (PEN) [10-13, 21, 23], LCP/polyester blends in a polyester matrix form in situ fibrils which improve the mechanical properties. LCPs have an inherently low melt viscosity, and provide LCP/polyester blends that effectively lower the melt viscosity during melt spinning [24], and fast injection-molding cycles. The miscibility between the LCP and polyesters can be controlled by the degree of transesterification [25] in the reactive extrusion step, and fibril formation in LCP-reinforced polyester fibers has been studied. 

Propanediol. Both the diol and the dicarboxylic acid components of poly-trimethylene-terephthalate, a high performance polyester fiber with extensive applications in textile apparel and carpeting, are currently manufactured from petrochemical raw materials. 

Toluene is used more commonly than the other BTXs as a commercial solvent. There are scores of solvent applications, though environmental constraints and health concerns diminish the enthusiasm for these uses. Toluene also is used to make toluene diisocyanate, the precursor to polyurethane foams. Other derivatives include phenol, benzyl alcohol, and benzoic acid. Research continues on ways to use toluene in applications that now require benzene. The hope is that the dealkylation-to-benzene or disproportionation steps can be eliminated. Processes for manufacturing styrene and terephthalic acid—the precursor to polyester fiber—are good, commercial prospects. 

Smaller volumes of methanol are used in the production of dimethyl terephthalate that goes into polyester fibers and in methyl methacrylate, which goes into plastics. 

Since the early 1970s p-xylene has grown to become a large volume petrochemical. It is used primarily for the production of polyester fibers, films and resins, such as PET (polyethylene terephthalate) [7]. Demand for p-xylene has increased tenfold since 1970 to about 26xl0 t/year. Almost all of this additional production has been by the UOP Parex process as shown in Figure 7.1. A baseline production ofp-xylene is maintained by crystallization based sites that existed before the SMB adsorptive separation technology was established [8]. 

Table 11.6 shows the uses of TA/DMT. TA or DMT is usually reacted with ethylene glycol to give poly(ethylene terephthalate) (90%) but sometimes it is combined with 1,4-butanediol to yield poly(butylene terephthalate). Polyester fibers are used in the textile industry. Films find applications as magnetic tapes, electrical insulation, photographic film, and packaging. Polyester bottles, especially in the soft drink market, are growing rapidly in demand. 

Aromatic polyesters had been successfully synthesized from the reaction of ethylene glycol and various aromatic diacids but commercialization awaited a ready inexpensive source of aromatic diacides. An inexpensive process was discovered for the separation of the various xylene isomers by crystallization. The availability of inexpensive xylene isomers allowed the formation of terephthalic acid through the air oxidation of the p-xylene isomer. DuPont produced polyester fibers from melt spinning in 1953, but it was not until the 1970s that these fibers became commercially available. 

R = (CH2 )2) and terephthalic acid (R/ = ), is familiar in the form of soda botdes, recording tape, and polyester fiber (see Fibers, polyester). 

POLYESTER FIBERS. The principal characteristics of these fibers are described in the endy on Fibers. Polyester fibers are defined as synthetic fibers containing at least 80% of a long-chain polymer compound of an ester of a dihydric alcohol and terephthalic acid. T he first polyester fiber to be commercialized was prepared from the ester in which the dihydric alcohol was ethylene glycol this fiber is the material used in the largest quantity bv the textile industry. For some other commercial uses, the ester 1,4-dimethyldicyclohexyl terephthalate is also used... 

TEREPHTHALIC ACID. CAS 100-21-01. Cf,H4(COOH)2, formula weight 166.13, crystalline solid sublimes upon heating, sp gr 1.510. The compound is almost insoluble in H2O, only slightly soluble in warm alcohol, and insoluble in ether. Terephtlialic acid (TPA) is a high-tonnage chemical, widely used in the production of synthetic materials, notably polyester fibers (poly-(ethylene terephthalate)). 

This is one of the most important industrial oxidation processes. Terephthalic acid (TPA) is mostly used for the manufacture of polyester fibers, films and plastics, and its world production capacity reaches 8 Mt/year. Two major processes have been developed. The Amoco-Mid Century process produces terephthalic acid by the one-step oxidation of p-xylene in acetic acid, whereas the Dynamit Nobel process yields dimethyl terephthalate in several steps and in the absence of solvent.83,84,86... 

Ethylene Glycol. Well over 50% of the ethylene oxide produced is used in the manufacture of ethylene glycol. Ethylene glycol [107-21-1] is used in two significant applications as a raw material for polyethylene terephthalate) for use in polyester fiber, film, and containers, and as an automotive... 

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