Polyester Fiber:
Polyester fibers are formed from synthetic polymers, manufactured by the action of polyfunctional acids with polyfunctional alcohols. The fiber-forming polymer substance is a long linear polymer with repeating ester groups in its structure. Polyester fiber is also known as Terylene, Terene, Dacron, etc. It is a manmade fiber of high polymers which are obtained by esterification of dicarboxylic acids, with glycols or by ester exchange reactions between dicarboxylic acid esters and glycols. Flow Chart of Polyester Fiber Production is as follows:
Flow Chart of Polyester Production
Preparation of raw material
(Terephthalic acid, DMT, ethylene glycol preparation)
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Mixing tank
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Polymerization in reactor
(Ester interchange and polycondensation, Temperature: 260-2800C, Time: 3-6 hours)
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Polymer chips
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Melt spinning
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Polyester filament produced from spinneret holes
(Monofilament, multifilament)
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Drawing
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Reeling onto a package or Texturization
Polyester is polymers made by a condensation reaction taking place between small molecules, in which the linkage of the molecules occurs through the formation of ester groups. Polyesters are commonly made by the interaction of a dibasic acid with dihydric alcohol:
HOOC-X-COOH + HO-Y-OH → …OC-X-COO-Y-OCO-X-COO-Y-OCO…
The formation of polyester was studied by Wallace H. Carothers of du Point during the investigation of polyesters which lead eventually to the discovery of nylon. The development of polyesters was overshadowed, however, by the polyamide research, and it was not until 1941 that a valuable polyester fiber was discovered. in that year, J. T. Dickson and J. R. Winfield of the Calico Printers’ Association England made a synthetic fiber from polyethylene terephthalate by condensing ethylene glycol with terephthalic acid.
After the war, the development of the fiber was carried out under license by I.C.I. Ltd. in the UK and du Pont in the USA, resulting in the fibers known respectively as ‘Terylene’ and ‘Dacron’. Today, polyethylene terephthalate fibers are being made in many countries, and modified forms of this fiber are also produced. Other polyesters have become of commercial importance.
Author of this Article: Muhammad Ibrahim Khalilullah Department of Textile Engineering Daffodil International University Email: [email protected]