Terylene terephthalate

Condensation polymerization differs from addition polymerization in that the polymer is formed by reaction of monomers, each step in the process resulting in the elimination of some easily removed molecule (often water). E.g. the polyester polyethylene terephthalate (Terylene) is formed by the condensation polymerization (polycondensation) of ethylene glycol with terephthalic acid ... 

The ethylene glycol liberated by reaction (5.L) is removed by lowering the pressure or purging with an inert gas. Because the ethylene glycol produced by reaction (5.L) is removed, proper stoichiometry is assured by proceeding via the intermediate, bis(2-hydroxyethyl) terephthalate otherwise the excess glycol used initially would have a deleterious effect on the degree of polymerization. Poly(ethylene terephthalate) is more familiar by some of its trade names Mylar as a film and Dacron, Kodel, or Terylene as fibers it is also known by the acronym PET. 

The windows of the absorption cell are made from polymer material such as polyethylene, poly(ethylene terephthalate Terylene ) or polystyrene. 

Poly(ethylene terephthalate), the predominant commercial polyester, has been sold under trademark names including Dacron (Du Pont), Terylene (ICI), Eortrel (Wellman), Trevira (Hoechst-Celanese), and others (17). Other commercially produced homopolyester textile fiber compositions iaclude p oly (1,4-cyc1 oh exa n e- dim ethyl en e terephthalate) [24936-69-4] (Kodel II, Eastman), poly(butylene terephthalate) [26062-94-2] (PBT) (Trevira, Hoechst-Celanese), and poly(ethylene 4-oxyben2oate) [25248-22-0] (A-Tell, Unitika). Other polyester homopolymer fibers available for specialty uses iaclude polyglycoHde [26124-68-5] polypivalolactone [24937-51-7] and polylactide [26100-51-6],... 

The successful development of polyfethylene terephthalate) fibres such as Dacron and Terylene stimulated extensive research into other polymers containing p-phenylene groups in the main chain. This led to not only the now well-established polycarbonates (see Chapter 20) but also to a wide range of other materials. These include the aromatic polyamides (already considered in Chapter 18), the polyphenylene ethers, the polyphenylene sulphides, the polysulphones and a range of linear aromatic polyesters. 

Linear polyesters were studied by Carothers during his classieal researches into the development of the nylons but it was left to Whinfield and Dickson to discover polyfethylene terephthalate) (BP 578079), now of great importance in the manufacture of fibres (e.g. Terylene, Dacron) and films (e.g. Melinex, Mylar). The fibres were first announced in 1941. 

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

Polymerisation of a diol with a dicarboxylic acid is exemplified by the production of a polyester from ethylene glycol and terephthalic acid either by direct esterification or by a catalysed ester-interchange reaction. The resulting polyester Terylene) is used for the manufacture of fibres and fabrics, and has high tensile strength and resiliency its structure is probably ... 

That fall, Carothers assistant Edgar W. Spanagel discovered polyethylene terephthalate, the polyester that Du Pont later manufactured under license as Dacron fiber and Mylar film. Carothers had made most of the polyesters, but he and others in his group assumed that Spanagel s polyester, like their earlier ones, melted at too low a temperature to be practical. As a result, Carothers did not have this one tested for spinnability. British scientists later used it to make Terylene. When Du Pont executives had to buy a license from the British to make Spanagel s fiber, their faces were bright red with embarrassment. 

A colourless, syrupy, sweet-tasting liquid the synthetic fibre Terylene is made by condensation polymerisation of terephthalic acid and ethylene glycol. 

In UK, in 1941, Whinfield and Dickson discovered the polyester fibre called terylene chemically it is polyethylene terephthalate. Teryene polymer can be melt spun into a fibre which is widely used in textile industry. 

The remarkable increase in the Melting point of polyesters formed by the incorporation of the aromatic ring is because of the stiffening of the polymer backbone. Thus, a polyester like polyethylene terephthalate (PETP) has a high Melting point due to the presence of the aromatic ring and is commercially the most popular polymers marketed under the trade name of Terylene or Terene. 

Uses Preparation of terephthalic acid for polyester resins and fibers (Dacron, Mylar, Terylene), vitamins, pharmaceuticals, and insecticides. Major constituent in gasoline. 

Poly(ethylene terephthalate), known by the trade names Mylar, Dacron, and Terylene, is a very high volume polymer—the United States production of PET fiber and plastic was over... 

One of the industrial processes using ZSM-5 provides us with an example of product shape-selective catalysis the production of l,4-( ara- xylene. Para-xylene is used in the manufacture of terephthalic acid, the starting material for the production of polyester fibres such as Terylene . 

Polyethylene, polypropylene, polyvinyl chloride, polyamide Phenol-formaldehyde-cured rubber styrenated polyester Polyimide (ladder molecules) Polyethylene terephthalate Terylene, cellulose acetate Chloroprene rubber, polyisoprene Heat-resistant polymers... 

Polyethylene terephthalate) in short PET is a polyester. It is mainly used in the garment industry with or without natural cotton and has trade names such as Terylene , Dacron , etc. As the name indicates, it is a polymer between terephthalic acid (PT) and ethylene glycol. Both terephthalic acid and dimethyl terephthalate (DMT) can be used to make the polymer. A majority of the modem plants tend to use PT as the starting material because of the availability of high-purity PT on a large scale. Both PT and DMT are first converted to bis(hydroxy ethyl) terephthalate 8.17 (see reaction 8.26). For PT this is effected by a straightforward esterification reaction. For DMT a transesterification reaction catalyzed by zinc and manganese acetate is used. 

Polyester fibers, similar to polyamide fibers, represent another important family of fiber. Polyester fiber was discovered in England in 1941 and commercialized in 1950. Two common trade names of polyester are Dacron in the US and Terylene in the UK. The term polyester fiber represents a family of fibers made of polyethylene terephthalate. Dimethyl terephthalate is reacted with ethylene glycol in the presence of a catalyst, antimony oxide, to produce polyethylene terephthalate or polyester. The chain repeat structure of PET is given in Fig. 4.6. Although polyesters can be both thermosetting and thermoplastic, the term polyester has become synonymous with PET. Note that the PET chain structure is different from the simpler structure of nylon or polyethylene. In PET, the aromatic ring and its associated C-C bonds provide a rigidity to the structure. The polyester structure is also bulkier than that of nylon or polyethylene. These factors make polyester less flexible than nylon and polyethylene, and the crystallization rate of PET slower than that of nylon or polyethylene. Thus, when polyester is cooled from the melt, an appreciable amount of crystallization does not result. 

Polyesters constitute a second major class of condensation polymers. The most common polyester is polyethylene terephthalate (PET), which is sold under a variety of trade names (Dacron, Terylene, and Mylar) depending on its use. 

Further reaction and water removal from this system will ultimately give polyethylene terephthalate, well known commercially in fiber form as Dacron, or Terylene, and as a film by the Mylar trade name (Eq. 20.5). 

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