At Goodyear Tire & Rubber’s proving grounds in San Angelo, Texas, sports cars snake through cones on wet pavement, dump trucks rumble down dirt roads, and semitrailers coast down long tracks. Each year, the company puts about 20,000 tires through these tests to evaluate their traction, toughness, and fuel efficiency.

Goodyear principal scientist Rob Dennis- Pelcher’s job is to identify a mix of tire materials that optimizes all these properties while decreasing the tire’s negative effects on the environment. It’s a difficult task. A modern tire might contain 20 components, including natural and synthetic polymers to form rubber, reinforcing fillers to increase strength, and additives to improve performance. “It’s really a balance of a lot of different factors,” says Dennis-Pelcher, who specializes in reinforcing filler materials like silica and carbon black.

Right now, many tire components are derived from petroleum, but Goodyear aims to produce a tire using all biobased, recycled, or otherwise sustainable materials by 2030. Dennis-Pelcher was part of a team that last year unveiled a demonstration tire made with 90% sustainable materials. The tire included carbon black derived from soybean oil and silica made from rice husks, among other materials. But tackling the other 10% of the tire’s ingredients—and ensuring a commercial version isn’t too expensive—will require an enormous amount of creativity.

“We use so much of these materials,” Dennis-Pelcher says. “Even if you develop a solution, getting it to scale and getting it to work across the board in all the applications we need can be quite complicated.”

Dennis-Pelcher scouts out ways to achieve these sustainability goals by talking with existing suppliers, identifying new collaborators with promising technologies, and scouring peer-reviewed papers and patents. In most cases, he can’t simply drop new materials into Goodyear’s manufacturing process. So he works with outside companies to refine their technologies and ensure their products won’t interfere with other tire chemicals.

In 2022, Dennis-Pelcher started working with Austin, Texas–based company Molecular Rebar Design (MRD) on a US Department of Energy–funded project to improve tire lifespan and energy efficiency using the firm’s dispersed carbon nanotubes. These nanotubes provide more reinforcement than conventional fillers like carbon black and silica, according to August Krupp, director of MRD’s rubber business. He says this feature will allow tire companies to use less filler material and make a more energy-efficient tire while improving structural integrity. Although MRD developed the carbon nanotube fillers, Dennis-Pelcher has published six patents proposing methods to improve the materials and incorporate them into tires. “It’s not just us innovating. He has to innovate too,” Krupp says.

Some of Dennis-Pelcher’s innovations are already on the road. Last year, Goodyear started selling tires that contain a more sustainable carbon black made by the firm Monolith. Conventional carbon black is produced by burning petroleum or coal tar, but Monolith uses renewable electricity to pyrolyze methane into hydrogen and carbon, avoiding carbon dioxide generated by combustion.

Ned Hardman, Monolith’s vice president and R&D fellow, says Monolith’s product contains less sulfur than conventional carbon black. Sulfur is a key element used to vulcanize, or harden, rubbers, and it can significantly affect tire chemistry. Hardman credits Dennis-Pelcher with tweaking Goodyear’s manufacturing process to account for the lower sulfur content, a task that required modifying several components at the same time. “Vulcanization science is beautiful chemistry, but it’s amazingly complex,” Hardman says. “That requires incredibly deep thinking.”

The tire industry still has a long way to go to achieve its sustainability goals. Goodyear, Michelin, and other tire makers have struggled to develop an inexpensive, biobased version of isoprene, a polymer used to make synthetic rubber. And the tiny particles tires fling into the air as they wear down remain a persistent source of pollution.

Overcoming those hurdles will require a variety of new technologies, so Dennis-Pelcher is constantly hunting for ideas with a glimmer of potential. Often, peer-reviewed papers or new patents don’t lay out a complete map to industrialization, so he must fill in the gaps by combining different chemistries and technologies. “That sparks my interest,” he says.