Polyester

Background

Polyester is a synthetic fiber derived from coal, air, water, and petroleum. Developed in a 20th-century laboratory, polyester fibers are formed from a chemical reaction between an acid and alcohol. In this reaction, two or more molecules combine to make a large molecule whose structure repeats throughout its length. Polyester fibers can form very iong molecules that are very stable and strong.

Polyester is used in the manufacture of many products, including clothing, home furnishings, industrial fabrics, computer and recording tapes, and electrical insulation. Polyester has several advantages over traditional fabrics such as cotton. It does not absorb moisture, but does absorb oil; this quality makes polyester the perfect fabric for the application of water-, soil-, and fire-resistant finishes. Its low absorbency also makes it naturally resistant to stains. Polyester clothing can be preshrunk in the finishing process, and thereafter the fabric resists shrinking and will not stretch out of shape. The fabric is easily dyeable, and not damaged by mildew. Textured polyester fibers are an effective, nonallergenic insulator, so the material is used for filling pillows, quilting, outerwear, and sleeping bags.

History

In 1926, United States-based E.I. du Pont de Nemours and Co. began research into very large molecules and synthetic fibers. This early research, headed by W.H. Carothers, centered on what became nylon, the first synthetic fiber. Soon after, in the years 1939-41, British research chemists took interest in the du Pont studies and conducted their own research in the laboratories of Calico Printers Association, Ltd. This work resulted in the creation of the polyester fiber known in England as Terylene.

In 1946, du Pont purchased the right to produce this polyester fiber in the United States. The company conducted some further developmental work, and in 1951, began to market the fiber under the name Dacron. During the ensuing years, several companies became interested in polyester fibers and produced their own versions of the product for different uses. Today, there are two primary types of polyester, PET (polyethylene terephthalate) and PCDT (poly-1, 4-cyclohexylene-dimethylene terephthalate). PET, the more popular type, is applicable to a wider variety of uses. It is stronger than PCDT, though PCDT is more elastic and resilient. PCDT is suited to the heavier consumer uses, such as draperies and furniture coverings. PET can be used alone or blended with other fabrics to make clothing that is wrinkle and stain resistant and retains its shape.

Raw Materials

Polyester is a chemical term which can be broken into poly, meaning many, and ester, a basic organic chemical compound. The principle ingredient used in the manufacture of polyester is ethylene, which is derived from petroleum. In this process, ethylene is the polymer, the chemical building block of polyester, and the chemical process that produces the finished polyester is called polymerization.

The Manufacturing
Process

Polyester is manufactured by one of several methods. The one used depends on the form the finished polyester will take. The four basic forms are filament, staple, tow, and fiberfill. In the filament form, each individual strand of polyester fiber is continuous in length, producing smooth-surfaced fabrics. In staple form, filaments are cut to short, predetermined lengths. In this form polyester is easier to blend with other fibers. Tow is a form in which continuous filaments are drawn loosely together. Fiberfill is the voluminous form used in the manufacture of quilts, pillows, and outerwear. The two forms used most frequently are filament and staple.

Manufacturing Filament Yarn

Polymerization

• 1 To form polyester, dimethyl terephthalate is first reacted with ethylene glycol in the presence of a catalyst at a temperature of 302-410°F (150-210°C).
• 2 The resulting chemical, a monomer (single, non-repeating molecule) alcohol, is combined with terephthalic acid and raised to a temperature of 472°F (280°C). Newly-formed polyester, which is clear and molten, is extruded through a slot to form long ribbons.

Drying

• 3 After the polyester emerges from polymerization, the long molten ribbons are allowed to cool until they become brittle. The material is cut into tiny chips and completely dried to prevent irregularities in consistency.

Melt spinning

• 4 Polymer chips are melted at 500-518°F (260-270°C) to form a syrup-like solution. The solution is put in a metal container called a spinneret and forced through its tiny holes, which are usually round, but may be pentagonal or any other shape to produce special fibers. The number of holes in the spinneret determines the size of the yarn, as the emerging fibers are brought together to form a single strand.
• 5 At the spinning stage, other chemicals may be added to the solution to make the resulting material flame retardant, antistatic, or easier to dye.

Drawing the fiber

• 6 When polyester emerges from the spinneret, it is soft and easily elongated up to five times its original length. The stretching forces the random polyester molecules to align in a parallel formation. This increases the strength, tenacity, and resilience of the fiber. This time, when the filaments dry, the fibers become solid and strong instead of brittle.
• 7 Drawn fibers may vary greatly in diameter and length, depending on the characteristics desired of the finished material. Also, as the fibers are drawn, they may be textured or twisted to create softer or duller fabrics.

Winding

• 8 After the polyester yarn is drawn, it is wound on large bobbins or flat-wound packages, ready to be woven into material.

Manufacturing Staple Fiber

In making polyester staple fiber, polymerization, drying, and melt spinning (steps 1-4 above) are much the same as in the manufacture of filament yarn. However, in the melt spinning process, the spinneret has many more holes when the product is staple fiber. The rope-like bundles of polyester that emerge are called tow.

Drawing tow

• 1 Newly-formed tow is quickly cooled in cans that gather the thick fibers. Several lengths of tow are gathered and then drawn on heated rollers to three or four times their original length.

Crimping

• 2 Drawn tow is then fed into compression boxes, which force the fibers to fold like an accordion, at a rate of 9-15 crimps per inch (3-6 per cm). This process helps the fiber hold together during the later manufacturing stages.

Setting

• 3 After the tow is crimped, it is heated at 212-302°F (100-150°C) to completely dry the fibers and set the crimp. Some of the crimp will unavoidably be pulled out of the fibers during the following processes.

Cutting

• 4 Following heat setting, tow is cut into shorter lengths. Polyester that will be blended with cotton is cut in 1.25-1.50 inch (3.2-3.8 cm) pieces; for rayon blends, 2 inch (5 cm) lengths are cut. For heavier fabrics, such as carpet, polyester filaments are cut into 6 inch (15 cm) lengths.

The Future

Following its introduction to the United States in 1951, polyester quickly became the country's fastest-growing fiber. Easy care of the permanent press fabric made polyester doubleknits extremely popular in the late 1960s. However, polyester has suffered an "image problem" since that time, and clothes made out of polyester were often devalued and even ridiculed. Several new forms of polyester introduced in the early 1990s may help revitalize the image of polyester. A new form of polyester fiber, called microfiber, was introduced to the public in 1991. More luxurious and versatile than traditional polyester, microfiber fabrics are difficult to tell apart from silk fabrics. Clothing designers such as Mary McFadden have created a line of clothes using this new form of polyester. Textile researchers at North Carolina State University are developing a form of polyester that may be as strong as Kevlar, a superfiber material used to make bulletproof vests. This type of polyester may eventually be used as composite materials for cars and airplanes.

Where To Learn More

Books

Corbman, Bernard P. Textiles: Fiber to Fabric. 6th ed. Gregg Division, McGraw-Hill, 1983, pp. 374-92.

Encyclopedia of Textiles. 3rd ed. Prentice-Hall, Inc., 1980, pp. 28-33.

Polyester: Fifty Years of Achievement. State Mutual Book & Periodical Service, 1993.

Periodicals

Fellingham, Christine. "Will You Learn to Love Polyester?" Glamour, April 1992, p. 204.

Templeton, Fleur. "Show Me a Bulletproof Leisure Suit, In Pink." Business Week, July 6, 1992, p. 65.

Thomas, Marita. "At 50 Years, Polyester Gains New Fashion Vitality." Textile World, December 1993, p. 62+.

—Kristine M. Krapp

POLYESTER

In 1929 Wallace Carothers, a researcher at DuPont, published an article describing his creation of polyester. DuPont obtained patents on this early form of polyester in 1931. Facing problems with this material, DuPont did not begin commercialization of it at that time, choosing instead to concentrate on the development of nylon. In the 1940s English researchers at Imperial Chemical Industries (ICI) developed the first practical version of polyester. It was made by combining ethylene glycol and terephthalic acid into polyethylene terephthalate (PET). DuPont bought the rights to PET in 1945 and began commercial production of Dacron polyester in 1953.

Polyester Defined

The Federal Trade Commission defines polyester as "a manufactured fiber in which the fiber-forming substance is any long-chain synthetic polymer composed of at least 85 percent by weight of an ester of a substituted aromatic carboxylic acid, including but not restricted to substituted terephthalic units, _p(–R–O–CO–C₆H₄–CO–O–)_x and parasubstituted hydroxyl-benzoate units, _p(–R–O–CO–C₆H₄–O–)_x" (Collier and Tortor, p. 179). The polyester most commonly used for fibers is PET.

Properties of Polyester

To the average consumer, who is not a chemist, polyester is an extraordinary fiber with many desirable properties. Polyester is strong, both dry and wet. It is considered to be easy-care since it can be washed, dried quickly, and resists wrinkling. It holds up well in use because it has high resistance to stretching, shrinking, most chemicals, abrasion, mildew, and moths.

As with all fibers, polyester has some properties that are not desirable. While resistant to water-born stains, polyester is an oil scavenger. Due to its strength, polyester, particularly when cut into short staple lengths, does form pills (becomes rough with little balls). Polyester will burn with a strong odor and the molten residue can cause severe burns to the skin. Because polyester has low absorbency, it can become uncomfortable in hot weather. This problem has been addressed by making polyester fibers with multilobal cross sections (as opposed to round ones). Since the multilobal fibers cannot pack together as tightly as round ones, perspiration can be wicked (carried on the surface of the fibers) away from the body, thereby improving the wearer's comfort.

Care of Polyester

Polyester is often blended with other fibers that require different care procedures. For this reason care procedures may vary across fabrics.

For 100 percent polyester fabrics, oily stains should be removed before washing. Generally they can be machine washed on a warm or cold setting using a gentle cycle. They can be tumble dried on a low setting and should be removed from the dryer as soon as the cycle is completed. Garments should immediately be either hung on hangers or folded. When handled in this way, fabrics made from 100 percent polyester rarely need ironing. If a touch-up is needed, it should be done at a moderate temperature on the wrong side of the fabric.

Some garments made from polyester or polyester blends may require dry cleaning. Tailored garments with multiple components, such as suits, may need to be drycleaned. It is important to follow care instructions and not assume that dry cleaning is better than washing. Pigment prints on polyester should not be dry cleaned, as the solvent would dissolve the adhesive that holds the pigment on the surface of the fabric.

Polyester's Image

When polyester first reached the market in the 1950s, it was hailed as a wonder fiber. Travelers could wash a garment, hang it up, and have it ready to wear in a couple of hours. It needed no ironing.

By the late 1960s, polyester's image was very different. Polyester leisure suits for men and polyester double knit pantsuits for women were embraced by the middle-aged and elderly. College students, on the other hand, hated polyester. In the 1970s they even referred to it as the "P" curse. They perceived it as cheap and certainly not "with it."

To combat this image, the Tennessee Eastman Company launched a "polyester" campaign to revive its image. The Man-Made Fiber Producers Association, which became the Manufactured Fiber Producers Association— Polyester Fashion Council, launched its own campaign. Both groups focused on polyester's easy-care properties instead of its cheapness. In 1984 the Man-Made Fiber Producer's Association and the Council of Fashion Designers endorsed collections made almost exclusively of polyester or polyester blends. Well-known designers, like Oscar de la Renta, Perry Ellis, Calvin Klein, and Mary McFadden, participated. Such publicity helped a little.

Probably a more important contributor to the improved image of polyester has been the technological advances made by the producers. High-tech fibers made of polyester have revolutionized the active sportswear market. Polyester microfibers are used to make fabric that feels like silk. Recycled PET polyester from soda bottles is transformed into comfortable fleece, thereby appealing to those concerned with the environment.

Uses of Polyester

Polyester could be called the tofu of manufactured fibers since its appearance takes on many forms. Depending upon the actual manufacturing process, polyester can resemble silk, cotton, linen, or wool. When blended with other fibers, polyester takes on even more forms, combining the good qualities of each contributing fiber. Polyester is also the most-used manufactured fiber. The DuPont company estimates that the 17.7 million metric tons consumed worldwide in 1995 will rise to almost 40 million metric tons by 2005.

Apparel uses of polyester. Polyester is used for all kinds of apparel, by itself and in blends. It is found in every type of clothing, from loungewear to formal eveningwear. Some common blends include polyester and cotton for shirts and polyester, and wool for suits. Polyester contributes easy-care properties to both of those blends while cotton and wool provide comfort. Another use of polyester fiber is found inside some garments. A ski jacket with hollow polyester fibers used between the outer fabric and the lining provides warmth without weight.

Home furnishings uses of polyester. Polyester and polyester blends are used for curtains, draperies, upholstery, wall coverings, and carpets, as well as for bedding. Sheets and pillowcases made from polyester and cotton blends, do not need to be ironed, but they are not quite as comfortable as those made from 100 percent cotton. Carpets made from 100 percent polyester are less expensive than nylon, more apt to get packed down with wear, and allow considerable build-up of static electricity during the dry winter months.

Other uses of polyester. Polyester's low absorbency and high strength even when wet make it ideal for umbrellas, tents, and sleeping bags. Some industrial uses of polyester take advantage of the same characteristics. Hence, polyester is used for hoses, tire cords, belts, filter cloth, fishing nets, and ropes. Polyester is used for sewing thread, but thread made of 100 percent polyester tends to heat up and form knots when used in high-speed sewing. Cotton-covered polyester thread eliminates the problem.

See alsoMicrofibers; Recycled Textiles .

bibliography

Collier, B. J., and P. G. Tortora. Understanding Textiles. 6th ed. Upper Saddle River, N.J. Prentice-Hall, Inc., 2001.

Humphries, M. Fabric Reference. 3rd ed. Upper Saddle River, N.J.: Pearson Education, Inc., 2004.

Internet Resource

Polyester Revival. 2004. Available from <http://schwartz.eng.auburn.edu/polyester/revival.html>.

Elizabeth D. Lowe

Polyester

The Frankenstein's monster of fabrics, polyester has enjoyed more lives than the evil baron's monstrous creation. The wonder fiber of the post-war West became the fashion rage of the superfueled 1970s. Then, dismissed and disavowed by the cognoscenti, it seemed on the verge of extinction until modern science resurrected its utility in the form of polar fleece in the 1990s. What a long, strange trip it's been.

Other than LSD, perhaps no man-made compound influenced the style of an era quite like polyester. And like LSD, it had its origins in a European laboratory. Polyester, the invention of two chemists working at the Calico Printers Association in England, was not the first man-made fiber. Rayon and Nylon had been in use for years as sportswear and stockings, respectively. But when J.T. Dickson and J.R. Whinfield hit upon a way to spin petrochemical molecules into threads, they created a fiber that was light years ahead in terms of its versatility and utility. The DuPont company sensed the commercial potential of the new invention and purchased the patents for it in 1950. Within three years, polyester was being produced in mass quantities.

Polyester's principal virtue was its plasticity. Natural fibers like cotton or wool cannot be re-engineered, but a man-made fabric like polyester can be custom designed to produce a different aesthetic. With advances in technology, new polyester blends were concocted that simulated the look and feel of "real" fabrics. Furthermore, because polyester is naturally permanently pressed, the need for irons and ironing boards was greatly reduced. DuPont even coined a term, "wash and wear," to describe the wondrous properties of its new synthetic.

Throughout the 1960s, polyester was sold to the public as the avatar of a new era of space age convenience in clothing. And for the most part, the people seemed to be buying it. Ads for "perma-prest," "wash-and-wear," and "double knit" items began dotting the pages of such barometers of public taste as the New York Times and the Sears catalog. In the 1970s, polyester pantsuits, leisure suits, and garishly-colored knit shirts stormed into fashion, as the fabric attained a kind of hipster cachet among suburban moderns. Poly blend sport shirts and flared slacks seemed the perfect attire for weekend barbecues, wife-swapping parties, and trips to the singles bar. Demand for the wonder synthetic became so great by 1974 that manufacturers had difficulty filling their orders.

What killed polyester? Like the fierce debate over "Who lost China?" in the 1950s, the question admits no easy answer. For one thing, there was the problem of ubiquity. By the late 1970s, polyester fashion had become so absorbed into the mainstream that it lost all claim on fashionable taste. Furthermore, with so much polyester on the market—and so much of it cheaply constructed—the fabric's inherent weaknesses began to assert themselves. Simply put, polyester does not breathe the way cotton does. The resultant tendency toward sweatiness gave the clothes a disagreeable downmarket connotation. Finally, the excesses of disco, as personified by John Travolta's egregious white polyester suit in the 1977 film Saturday Night Fever, put the final nail in the wonder fabric's coffin.

For almost two decades, polyester languished in popular disrepute. Occasionally used in blends in order to make clothes less expensive, it was all but shunned as an emblem of poor taste by anyone with a shred of fashion sense. Camp film director John Waters even titled his 1981 celebration of tackiness Polyester. In the mid-1990s, however, the miracle fiber began to make a comeback in the form of polar fleece. Best known under the trade name Polartec, the fabric was marketed in the form of sweaters, leggings, hats, and mittens by such hip winter wear outfitters as Patagonia and Lands' End. Once again, polyester's utility was the major selling point. Polar fleece is lightweight and does not absorb as much water as other fabrics, making it the perfect lining for outerwear.

And as it had in the 1950s, utility begat fashionability. By 1998, top designers such as Donna Karan and Tommy Hilfiger were integrating polar fleece into their clothing lines. While it was perhaps too early to declare polyester completely rehabilitated, the popularity of winter sports and the rise of casual chic seemed to assure the continued marketability of polar fleece into the new millenium. The wonder fabric's most remarkable attribute, it seemed, was its indestructibility.

—Robert E. Schnakenberg

Further Reading:

Stern, Jane, and Michael. The Encyclopedia of Bad Taste. New York, Harper Collins, 1990.

Polyester

Like nylon (see entry under 1930s—Fashion in volume 2), polyester heralded a brave new world of fabrics and fashion after World War II (1939–45). Woven in bright colors and strange textures, polyester was the defining fabric of 1960s and 1970s fashion. As a result, when polyester went out of fashion in the late 1970s, it all but disappeared from view. Throughout the 1980s, polyester was something of a joke. Memories of the convenience of "wash and wear," minimal-iron shirts, were tinged with the shame of body odor and fashion tragedy. It was only with the rise of outdoor chic that polyester, in the form of polar fleece, garnered popularity again.

Polyester was the invention of two chemists working for the Calico Printers Association in England. J. T. Dickson and J. R. Winfield worked out a way to spin plastics made from petro-chemicals. The DuPont company bought the patents in 1950, and the wonder fabric was launched. As the technology advanced, polyester was blended to make fabrics that looked and felt like cotton or wool. Although these copies were never very good, none of it mattered. In the 1960s and early 1970s, polyester was the height of cool suburban fashion. Flared slacks, knit shirts, and "pantsuits" graced the barbecue party, the workplace, and malls (see entry under 1950s—Commerce in volume 3).

By the late 1970s, polyester was everywhere. It flooded the market in such quantities that it lost its fashionable edge. When that happened, people began to notice that polyester made them sweat. Put politely, when everybody wore polyester, the atmosphere could become unpleasant. Polyester's status as the tackiest of fabrics was confirmed in 1981 when director John Waters (1946–) called one of his bad-taste films Polyester. In the 1990s, re-engineered and sold under the trade name Polartec, polyester made a comeback. Its light weight, and the fact that it does not absorb water, made polar fleece ideal for skiers, hikers, and other fans of the outdoors. By the late 1990s, top fashion labels such as Tommy Hilfiger (1952–) used it in their fashion ranges. In 2001, polyester has become one of the most comfortable, fashionable, and practical of all synthetic fabrics.

—Chris Routledge

For More Information

Smith, Matthew Boyd. Polyester: The Indestructible Fashion. (Schiffer Book for Collectors and Designers). Atglen, PA: Schiffer, 1998.

Stern, Jane, and Michael Stern. The Encyclopedia of Bad Taste. New York: HarperCollins, 1990.

Polyester ★★½ 1981 (R)

Amusing satire on middleclass life, described by producer, director and writer Waters as “'Father Knows Best' gone berserk.” Forlorn housewife Divine pines for the man of her dreams while the rest of her life is falling apart at the seams. Filmed in “Odorama,” a hilarious gimmick in which theatre goers were provided with scratchnsniff cards, containing specific scents corresponding to key scenes. Video watchers will have to use their imagination in experiencing a wide range of smells. The first of Waters' more mainstream films. Features songs by Murray and Harry. 86m/C VHS, DVD . Divine, Tab Hunter, Edith Massey, Mink Stole, Stiv Bators, David Samson, Mary Garlington, Kenneth King, JoniRuth White, Jean Hill, Hans Kramm, Mary Vivian Pearce, Cookie Mueller, Susan Lowe, George Stover, George Figgs, Steve Yeager; D: John Waters; W: John Waters; C: David Insley; M: Deborah Harry, Michael Kamen.