The Power of Polymers
Throughout history, innovative humans have developed technology to overcome or adapt to challenges in the natural world. As it turns out, some of our most important advances were actually inspired by a naturally occurring group of materials: polymers.
Derived from Greek words meaning “many parts,” the word polymer refers to a large molecule composed of multiple repeating units. This structure makes polymers strong, but lightweight, and flexible—properties that come in handy for a wide range of purposes.
Unknown to most people, natural polymers include cotton, wool, leather, and silk, which have been used to make clothing for thousands of years. Silk, produced naturally by insects, was even deployed in military conflicts. Lightweight, but impenetrable to arrows, woven silk undergarments helped Mongol invaders sweep across Europe and defeat knights wearing heavier metal armor as far back as the 13th century. During the U.S. Civil War, clothing makers added cellulose—a building block of plant cells—to military uniforms.
As scientists studied polymers, they found different ways to use or improve them. For example, experiments demonstrated that adding sulphur to cellulose, a process known as vulcanization, created a polymer that was less sticky, enabling production of rubber hoses, gloves, belts, and more.
Those successes helped inspire a multitude of manmade polymers that we know today, including rayon, nylon, plastics, and Teflon. Kevlar, developed 50 years ago, is lightweight and flexible, but super-strong. Today, you can find it in products ranging from bicycle tires to mooring lines and body armor.
Other polymer-based products make our lives easier and safer. They reduce energy costs and enable medical advances. Some examples include shatterproof windshields, lightweight composite materials in airplanes, and stitches that gradually dissolve after they are applied to a wound.
Researchers continue to discover new, powerful ways to use polymers. In fact, the 2000 Nobel Prize for chemistry was won by a team of scientists who discovered that polymers can be modified to conduct electricity. This could support innovative products ranging from organic solar cells and light-emitting diodes to next-generation coatings on stealth aircraft. Conductivity could also enable smart textiles, which would mimic human skin by reacting to electrical signals like temperature change. Printing miniature electric circuits on clothing could allow it to monitor the wearer’s vital signs, and even call for help in the event of an emergency.
And at the University of Illinois at Urbana-Champaign, scientists have synthesized a self-healing polymer, which might one day make spacecraft less reliant on human repairs. Imagine a coat of paint on a house that repairs its own cracks, or having your favorite shirt mend itself after snagging on a nail. Self-healing polymers might even make buildings more resilient, better able to withstand earthquake damage.
It’s also important to consider the environmental impact from polymer products. For example, most plastics are not biodegradable, and since we currently recycle only a fraction of what we create, too much ends up in landfills or in the natural environment. Going forward, we’ll need to improve our disposal and recycling performance and consider new technologies that accelerate the biodegradation of obsolete materials.
Ultimately, polymers have reduced our dependence on scarce natural resources, including wood from trees and metals which must be mined and processed. And the reduced weight of polymer-based containers compared to glass and metals helps conserve fuel used for transportation, reducing pollution.
The benefits of polymers are enormous and many are still being discovered. Continuing research will deliver innovations that improve our lives both in the near future and for many years to come.