thumb|Elastic material used in the fabrics of a summer [[cycling kit|cycling attire comprising a jersey, bib shorts and gloves]]

Spandex, Lycra, or elastane is a synthetic fiber known for its exceptional elasticity. It is a polyether-polyurea copolymer that was invented in 1958 by chemist Joseph Shivers at DuPont.

thumb|Colourless spandex yarn

Name

The name spandex, which is an anagram of the word "expands", is the preferred name in North America. In continental Europe, it is referred to by variants of elastane. It is primarily known as Lycra in the UK, Ireland, Portugal, Spain, Latin America, Australia, and New Zealand.

Brand names for spandex include Lycra (made by The Lycra Company, previously a division of DuPont Textiles and Interiors), Elaspan (The Lycra Company), Acepora (Taekwang Group), Creora (Hyosung), INVIYA (Indorama Corporation), ROICA and Dorlastan (Asahi Kasei), Linel (Fillattice), and ESPA (Toyobo).

Production

Unlike many other synthetic fibers, spandex cannot be melt-processed because the polymer degrades upon melting. Spandex fibers are produced by several spinning technologies. Typically, a concentrated solution of the polymer is drawn through spinnerets at temperatures where the solvent evaporates.

thumb|Chemical route to polyurethane polymer used in production of spandex|434px

Spandex is mainly composed of a polyurea derived from the reaction of a diol and a diisocyanate. Two classes of spandex are defined by the "macrodiols". One class of macrodiols is the oligomer produced from tetrahydrofuran (i.e. polytetrahydrofuran). Another class of diols, the so-called ester diols, are oligomers derived from condensation of adipic acid and glycols. Spandex produced from the ester diols is more resilient photochemically and to chlorinated water. Almost always, the diisocyanate is methylenebis(phenyl isocyanate). The key linking reaction is formation or the urea (aka urethane):

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The polyurea is usually treated with various diamines, which function as chain extenders.

Function

The exceptional elasticity of spandex fibers increases the clothing's pressure comfort, enhancing the ease of body movements. Pressure comfort is the response towards clothing by the human body's pressure receptors (mechanoreceptors present in skin sensory cells). The sensation response is affected mainly by the stretch, snug, loose, heavy, lightweight, soft, and stiff structure of the material.

The elasticity and strength (stretching up to five times its length) of spandex has been incorporated into a wide range of garments, especially in skin-tight garments. A benefit of spandex is its significant strength and elasticity and its ability to return to the original shape after stretching and faster drying than ordinary fabrics. For clothing, spandex is usually mixed with cotton or polyester, and accounts for a small percentage of the final fabric, which therefore retains most of the look and feel of the other fibers. An estimated 80% of clothing sold in the United States contained spandex in 2010.

<gallery caption="Stretch material used in various sports" mode="packed" heights="200px">

Athlete.png|A road cyclist wearing compression garments

Hurdler.jpg|A United States Air Force Academy hurdler in a uniform

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History

The easy condensation of diols and diisocyanates was recognized in the 1930s as the result of work by Otto Bayer. At this time, women began to emerge as a significant group of consumers because of their need for underwear and hosiery. <!--Determined to find a fiber to replace rubber in garments, after nearly a decade of research, Shivers perfected the fiber in 1958 at DuPont's Benger Laboratory in Waynesboro, Virginia.--> DuPont launched an extensive publicity campaign for its Lycra brand, taking advertisements and full-page ads in top women's magazines<!-- such as Vogue, Glamour, Harper's Bazaar, Mademoiselle, McCall's, Ladies' Home Journal, and Good Housekeeping-->.

By the mid-1970s, with the emergence of the women's liberation movement, girdle sales began to drop as they came to be associated with anti-independence and emblematic of an era that was quickly passing away. The fiber came to be especially popular in mid-thigh-length shorts worn by cyclists. Spandex proved such a popular fiber in the garment industry that, by 1987, DuPont had trouble meeting worldwide demand. In the 1990s a variety of other items made with spandex proved popular, including a successful line of body-shaping foundation garments sold under the trade name Bodyslimmers. As the decade progressed, shirts, pants, dresses, and even shoes were being made with spandex blends, and mass-market retailers like Banana Republic were even using it for menswear.

On March 17, 2026, The LYCRA Company LLC and 25 affiliated debtors each filed a voluntary petition for relief under Chapter 11 of the United States Bankruptcy Code in the United States Bankruptcy Court for the Southern District of Texas.

Environmental impact

Most clothes containing spandex are difficult to recycle. Even a 5% inclusion of spandex will render the fabric incompatible with most mechanical recycling machines.

Notes

References

  • "What's That Stuff: Spandex" Chemical and Engineering News