In our changing world, technological advances seem to come at us every day. Some are introduced gradually into our lives, such as the various types of alternative fuels, and some come unexpectedly.

One technological advance that grabbed my attention recently is the development of materials aimed at replacing the rubber tire we are all so familiar with.

Amerityre Corp. in Boulder City, Nev., has developed new compounds that, when blended, create a polyurethane tire that the company says runs cooler, lasts longer and costs no more than a standard rubber tire. It is also clean to manufacture and clean to dispose of, Amerityre says.

The prospect of a tire that could run for 100,000 miles or more, could run fl at for extended periods with no compound deterioration, and is environmentally friendly was more than enough to pique my interest.

Is it a contender?
I contacted Guy Walenga at Bridgestone Firestone, a longtime manufacturer of rubber tires, and asked for his thoughts on the development of the polyurethane tire. While he expressed skepticism that Amerityre’s technology is commercially viable at this point, he acknowledged that there are benefits to using polyurethane in tires: lighter weight, good resistance to wear, easy to manufacture in colors.

However, Walenga said that polyurethane tires would not measure up to current rubber pneumatic tires in terms of cornering, braking and traction performance.

Amerityre begs to differ, saying that its tires pass all performance testing with a “B” classification, which is only slightly less than perfect. The company also said that it recently passed the grueling government standards for tires, FMVSS 109 and FMVSS 139, the latter of which became effective in September 2007.

In actual road testing, a late model Chevrolet Corvette was outfitted first with standard rubber compound tires and then with polyurethane tires. The driver of the car noticed no difference in cornering, handling or performance, according to Amerityre.

Dave Martin of Amerityre said that the polyurethane tire is not affected by UV light. This means it would not experience the casing deterioration that the sun can cause in current rubber formulated tires. Additionally, oil does not penetrate polyurethane.

Keep it clean
The manufacturing process includes mixing compounds together much like you would mix together epoxy parts A and B to achieve the final cured product. Although there is much more involved in the polyurethane tire than that, the process is very clean. Less than 1 percent is wasted during the manufacturing process, all of which is 100-percent recyclable.

The tires are poured into a mold and then allowed to cure. I asked Martin how a tire can be poured into a mold without developing imperfections. He said that Amerityre uses a vacuum in the process, which removes any voids. Tires come out of the mold perfectly round and true, Martin said, requiring no machining to make them balanced.

It is also interesting to note that polyurethane tires could be manufactured in any color — even clear — and virtually any tread design could be built into them. However, Martin noted that the practicality of a colored tire would be slim unless it was a special order for a custom application, and this would increase the cost since one-time compounds would have to be used.

In the works
Amerityre’s current production is focused on automotive tires, but the company is in the development stages of a polyurethane retread for a rubber casing truck tire.

Gary Benninger, president and CEO of Amerityre, said that the retread is undergoing lab tests and should be ready for real-world tests within a few months. He said that he hopes this new development will be on the market within the next year.

After that, Benninger said, Amerityre’s efforts will shift toward a dedicated polyurethane truck tire. Then, the company will branch out into other modes of transportation.

For more information on Amerityre’s polyurethane technology, go to www.amerityre.com.