The Forgotten History of Synthetic Fibers: How Chemistry Reshaped What We Wear

For roughly ten thousand years before 1935, the materials humans wore came from four sources: cotton, linen, wool, and silk. Plus a handful of regional fibers — hemp, jute, ramie — but in essence, four fibers, each tied to a specific organism with its own range of climates and seasons and constraints. The yardage of cloth produced globally was bounded by the carrying capacity of farmland and pastureland for cotton, flax, sheep, and silkworms. Clothing was relatively expensive and a household typically owned three to five sets of clothes that lasted years and were patched repeatedly.

Between 1935 and 1958, organic chemistry produced four entirely new fiber families that did not exist in nature: nylon, polyester, acrylic, and spandex. None of them came from organisms; all came from petrochemical feedstocks via reactions that did not occur outside laboratories. Within thirty years, synthetic fibers accounted for over half of global fiber production. By 2010 the figure was over two-thirds. The transformation was the largest material change in human textile history, and most people do not know when or where it happened.

Nylon, 1935

Wallace Carothers joined DuPont's new fundamental research lab at Wilmington in 1928 with a brief to investigate polymerization. He was thirty-two, a chemist of uncommon talent, depressive, and willing to pursue work whose commercial value was unclear. His first six years produced neoprene synthetic rubber and a series of polyamides that DuPont's commercial side could not figure out what to do with. In 1935 his team produced polyamide 6,6 — a long-chain molecule formed by condensing hexamethylenediamine with adipic acid — and discovered that fibers drawn from the melt and cold-stretched had remarkable strength and elasticity.

The commercial opportunity was women's stockings, then made of silk imported almost entirely from Japan. By 1939 DuPont had built a production plant at Seaford, Delaware. Nylon stockings went on sale on May 15 1940. Four million pairs sold in the first day. Carothers had killed himself two years earlier with potassium cyanide; he never saw the product launch.

World War II diverted nylon to parachutes, ropes, and other military uses, creating a domestic shortage that became part of the cultural memory of the period — the gift of nylon stockings was a recurring trope in films and novels of the late 1940s. Postwar production scaled rapidly, and by 1950 nylon was found in carpets, fishing line, surgical sutures, and a hundred other applications no one had imagined when the molecule was first synthesized.

Polyester, 1941

The polyester chemistry was developed at Calico Printers Association in Manchester by John Whinfield and James Dickson in 1941, working from Carothers's earlier polyester research that DuPont had abandoned as commercially unpromising. The molecule — polyethylene terephthalate, or PET — was patented during the war and licensed to ICI in Britain (which sold it as Terylene) and DuPont in the US (which sold it as Dacron starting in 1953).

Polyester's commercial story took a decade longer than nylon's because the early product had problems that nylon did not. It was uncomfortable against skin, it pilled badly, and it did not take dyes well. The fixes — better dyeing technology, blending with cotton, finer fiber denier — accumulated through the 1950s and 1960s. By 1971 polyester production exceeded cotton production in the US for the first time. The polyester double-knit suits and dresses of the 1970s became a cultural shorthand for tackiness, but the underlying chemistry continued to improve, and modern athletic wear, fleece, and microfiber are all polyester variants that solve the comfort problems of the original.

The same molecule found a second commercial life in plastic bottles. PET soda bottles, introduced in 1973, are made of the same chemistry as polyester fiber, processed slightly differently. The recycled-bottle-to-fleece supply chain is the same molecule going around the cycle again.

Acrylic, 1944

DuPont's Orlon, the first commercial acrylic fiber, was developed during the war and launched in 1950. Acrylic chemistry is polyacrylonitrile, made by polymerizing acrylonitrile monomer. The fiber was developed as a wool substitute: it has similar bulk and warmth properties, takes dyes well, and does not have wool's tendency to shrink and felt in machine washing. Acrylic became the dominant fiber in sweaters, scarves, blankets, and synthetic fur through the 1960s and 1970s.

Acrylic's chemical structure also turned out to be the precursor to carbon fiber. When acrylic is heated under tension in an oxygen-free atmosphere, the long carbon backbone reorganizes into the layered graphite-like structure of carbon fiber. Most carbon fiber produced today starts as polyacrylonitrile fiber, then is carbonized in a multi-step thermal process. The connection between sweaters and aerospace components is closer than it appears.

Spandex, 1958

Spandex — or elastane in Europe, or Lycra under the DuPont brand — was developed by Joseph Shivers at DuPont and patented in 1958. The chemistry is segmented polyurethane: a long-chain molecule with alternating soft and rigid segments. The soft segments give the fiber its elasticity (it can stretch to 500% of its resting length and return) while the rigid segments give it dimensional stability. The fiber is rarely used alone; it is blended with other fibers at low percentages (2-20%) to give woven and knitted fabrics elasticity that the base fiber cannot provide.

Spandex is the smallest of the four by volume but its impact is structural. Before spandex, woven fabrics were stretchy only to the extent that the weave allowed. After spandex, almost any fabric could be made elastic by blending in a small percentage. Modern athletic wear, swim wear, denim, and form-fitting clothing all depend on spandex blends. The fact that jeans now stretch and recover, where 1960s jeans did not, is spandex doing its work invisibly.

What the transformation enabled and cost

The volume effect is enormous: synthetic fibers decoupled clothing production from agricultural land. A nylon plant on a few acres produces fiber that would have required millions of acres of cotton or sheep pasture. The economic effect is that clothing has become cheap relative to historical norms. In 1900 a US household spent roughly 14% of its income on clothing; in 2020 the figure was around 3%. The wardrobe has expanded correspondingly: where households once owned three to five sets of clothes, they now own dozens.

The environmental costs are real and were not anticipated. Synthetic fibers shed microfibers in washing that end up in oceans and food chains. Their petrochemical origin links clothing to fossil-fuel extraction. Their persistence — a polyester garment in a landfill takes hundreds of years to decompose — means the fiber accumulates in ways that natural fibers do not. The fast-fashion industry that synthetic fibers enabled has its own labor and waste implications.

The deeper observation

The synthetic fiber revolution is one of the largest material transformations in human history and one of the least remembered. We do not have founding-myth stories about Carothers the way we do about Edison or Bell, we do not teach polymerization in high school chemistry except as an example, and most people wearing synthetic fibers do not know what they are made of or when they were invented. The pattern is not unique — most foundational chemistry sits in this kind of public obscurity — but it is striking that something that touches every human body every day went from impossible to ubiquitous in a single working career and the working career was almost entirely forgotten.