Nailed it: Bridgestone, Dow partner for self-healing tire tech

AKRON—There's something to be said about the proverbial Olympic spirit, a spirit that fosters collaboration, innovation and a focus on a healthier planet.

So perhaps it comes as no surprise that two Olympics partners—themselves giants operating in the tire and rubber spheres—have tapped that spirit of teamwork and innovation for the development of a more sustainable tire-sealing solution: B-Seal S.

Developed in tandem by both Bridgestone Americas Inc. and Dow Inc. over the last four years, B-Seal S is heralded as the world's first self-healing and recyclable silicone-based tire sealant. It's a product that Bridgestone believes can change the game for a tire industry rapidly evolving around both electrification and sustainability.

"We envision a future where tires are the ultimate enablers of sustainable mobility," Nizar Trigui, Bridgestone Americas' chief technology officer and group president of Solutions Businesses, said of Bridgestone's vision for safer, more reliable tires. "… Our collaboration with Dow demonstrates how we're using innovation and collaboration to make mobility safer, more efficient and more sustainable."

B-Seal S is applied to the tire during the manufacturing process, after the tire has been cured. The two-part solution is "ribboned in" at room temperature and cures once it is applied to the inside of the tire, Bob Lux, Bridgestone's director of consumer engineering, told Rubber News.

The application process itself is part of the B-Seal S appeal from a sustainability standpoint, especially when compared to more traditional natural-rubber- or butyl-based sealants, which need to be heated when applied. That application difference alone helps to reduce the ecological footprint of B-Seal S, Lux said.

"The other solutions out in the market are butyl and natural rubber, and we knew some of the shortcomings," Lux said. "The idea was: How can we come up with an idea that has better footprint, one that has less of an energy requirement, and one that is going to have better sustainability?"

The answer? Develop a product that can be easily recycled. And B-Seal S, Lux said, does just that.

Dow is developing processes to recycle silicones—and B-Seal S, specifically, Lux said.

Meanwhile, the ability of B-Seal S to easily be removed from the lining of the tire allows for more efficient tire recycling.

"When you go for the traditional recycling of tires, you have to a bunch of basically shredders that the tires are going through," Lux said. "And when you have bunch of sealant tires that are going through—silicone, butyl, natural rubber—it gums up those knives. That piece of rubber just kind of balls up and they have to stop and go back in and clean out the shredder."

With an understanding that tires with self-healing sealants will become more prevalent as EVs continue to gain market share, the need for more efficient tire recycling capabilities becomes more evident, Lux said.

He believes that B-Seal S is a significant part of that solution.

Bridgestone sees B-Seal S filling a critical reliability gap for an auto industry that has gone all-in on the development and production of electric vehicles. Because unlike their internal combustion engine predecessors, EVs—with their overall weight and torque—place a much greater burden on the tires that connect them to the roadways.

To help extend EVs ranges and maximize their efficiency in the process, auto makers are looking to cut as much weight as possible from the vehicles powered ultra-heavy battery packs.

Spare tires was among the first things to go.

And that means that OEMs are going to rely heavily on solutions that allow tires to self-heal after punctures.

"Sealant is becoming more and more of an option because it has fewer tradeoffs from a rolling resistance standpoint, which is really important for BEVs with range. It is really important just for the overall weight of the vehicle," Lux said. "… As the industry is going to be going more and more toward some kind of extension solution, we see sealant as a potential for gaining market share and having wider selection of tires in the marketplace."

Sealant will be a key alternative even to run-flat tires, Lux said. The overall weight of EVs is the Achilles heel for run-flat tires, which are limited by their load index.

Run-flats do have an advantage when it comes to cracks or tears in the sidewalls, Lux said, so it's likely some combination of the run-flat and seal-sealing technology will be needed to create a better balance for tire makers, auto makers and consumers.

That said, it won't be long before the B-Seal S technology makes its way onto U.S. highways, city streets and country roads. By mid-2023, consumer are likely to see B-Seal S rolled into some of Bridgestone's premium products, particularly those that are OE fitments.

"Like everything in the automotive industry, a lot of our technology really starts with the OEMs," Lux said.

Although he could not provide specifics, Lux noted that Bridgestone is working closely with an OEM partner on the B-Seal S technology, and is poised to bring the product to the market in the months ahead for at least one of the auto maker's forthcoming BEV models.

Bridgestone already has the equipment and technology available for full-scale production of tires utilizing the B-Seal S technology. And the company is eager to move forward.

"This fits our commitment to being carbon neutral by 2050 and have a sustainable tire portfolio by that time," Lux said. "By the end of this decade (we plan to) have a 40-percent sustainable tire from a material circularity number, that is vs. where we were at in 2011. That all goes into the essence of where Bridgestone is.

"We look at what Bridgestone stands for, and what we are really trying to do is go out and get the best technology and best ideas from partnerships that we can, and bring that technology in and use our technology and expertise to meld that together to come up with new solutions," Lux said.

In this case, Bridgetsone brought the tire expertise. Dow brought the silicone expertise.

"It's exciting to see where this whole industry is going and how quickly it is going to go," Lux said. "And (it's exciting) to know that our team has worked on something that is going to be a sustainable answer as we are moving into that future."