Fiber used for bullet-proof vests resists punctures in Goodyear's tires

It puts a sturdy snap in a snare drum’s beat, produces good vibrations as a woodwind’s reed and can stop a speeding bullet when woven into a vest. Known as Kevlar, the lightweight para-aramid synthetic fiber is said to be five times stronger than steel. Developed in 1965 by DuPont scientist Stephanie Kwolek, Kevlar was first used commercially in the 1970s as a replacement for steel in racing tires. Since then, engineers at Goodyear and DuPont have collaborated on expanding its mobile applications.

Tires with Kevlar fiber are targeted for use in conditions ranging from rough, rocky terrain to everyday highway driving, and the material can help provide stability, toughness and comfort, according to Jon Bellissimo, Goodyear’s North American director of consumer tire technology.

“In recent years, we have been using components such as (Kevlar and other engineering innovations) to develop tires that provide relevant benefits to consumers,” says Bellissimo.

“In our extreme off-road tires, the reinforced sidewalls with Kevlar help increase sidewall puncture resistance. I believe the Kevlar name also strikes a responsive chord among off-road enthusiasts because of the inferred toughness and the tire’s ability to maneuver on and in many different surfaces,” he points out.

“DuPont has been working with Goodyear for years to help develop tires that are high-performing,” says Thomas G. Powell, vice president and general manager for DuPont Protection Technologies.

“For more than 40 years, (Kevlar) has been recognized worldwide for its proven performance in a wide variety of safety and high performance applications, including automotive and tires; body armor and protective apparel; aerospace and airplane components; and energy solutions,” Powell reports. “We continue to focus on reinventing our offering with new technologies that make a difference in everyday life.”

Using DuPont’s knowledge of material properties, the synthetic yarns are designed and developed into cords to meet Goodyear’s tire performance needs for cars, trucks and aircraft, Bellissimo explains.

“The material property advantages of Kevlar are extensively used globally in developing new tire concepts that help deal with the challenges of the road, ride and comfort, handling, thermal and flame resistance, reduced tire weight and road noise, among others,” he says.

“In addition, development compounds are processed globally each year with Kevlar Engineered Elastomer (EE) to optimize the mixing process and reinforcements of the different rubber parts of a tire to meet performance goals,” Bellissimo notes.

In 2005, Goodyear introduced Wrangler and Fortera tires with SilentArmor Technology, featuring a layer of the material under the tread to promote toughness while delivering a smooth and quiet ride.

The Eagle with ResponsEdge Technology tire, released in 2006, has a sound- and shock-absorbing InsuLayer made with Kevlar.

Bellissimo says the new Wrangler MT/R with Kevlar is “the first off-road tire in the U.S. built with the rugged toughness” of the fiber to produce enhanced sidewall puncture resistance.

“The use of Kevlar helps provide sidewall cut- and puncture-resistance to an area of the tire that demands extra toughness when driving off-road. It also helps reinforce the sidewall for when drivers return to the pavement for the drive home. Sidewalls reinforced with Kevlar in the new tire help increase sidewall puncture resistance by approximately 35 percent, compared to the original Wrangler MT/R, a tire already well-known for its toughness,” according to Bellissimo.

Goodyear subsidiary Dunlop, working with designer Pininfarina, has unveiled an ultra-lightweight concept tire featuring the latest Kevlar technology to replace traditional steel components. At 20 percent less weight, the tire aims for better fuel economy combined with increased performance and heightened driving pleasure.

“Such an enormous weight reduction would lead to significant lower levels of rolling resistance and fuel consumption,” says Bernd Loewenhaupt, director of Dunlop’s consumer tire technology.

The Dunlop SP Sport Maxx TT, featuring Kevlar-reinforced lower sidewalls, “is a new tire that helps empower drivers by enhancing driver feedback and precision. A motorsports-inspired tread and Dunlop’s exclusive Touch Technology combine to help deliver strong grip and steering response,” reports Razvan Bosomoiu, the company’s general manager.

The tire “helps deliver great road feel, which is important for those who really love to drive. The timely feedback from these tires allows the driver to react to turns and contours in the road,” Bosomoiu says. It is available now in North American consumers in 35 initial sizes, ranging from 16- to 22-inch rim diameters, and also is being launched this summer in Europe.

For more information, visit www.dunloptires.com, www.goodyeartires.com and www.dupont.com.