(From the May 14, 2012, issue of Rubber & Plastics News)
HILTON HEAD, S.C.—Executives from three startup companies—two with innovative tire designs, another with a plan to make tire-grade guayule rubber in commercial quantities—sought backers for their businesses at the Clemson University Tire Industry Conference in Hilton Head April 18-20.
Avishay Novoplanski, founder and chief technical officer of Israeli firm Galileo Wheel Ltd., said his company's patented “CupWheel” tire design offers a substantial advance in performance and durability over traditional pneumatic tires.
“Bias and radial tires are both a kind of envelope filled with a volume of air,” Novoplanski said. “The main role of a tire is to absorb shock. If a tire is flexible vertically, it's also flexible sideways, a tradeoff all tires suffer from.”
However, the CupWheel design obviates that tradeoff, eliminating some of the boundaries of traditional tire design, according to Novoplanski. “We are breaking design limits where shock absorption and ride comfort no longer contradict side stability,” he said.
Because CupWheel tires require very little air, they have an integral run-flat capability, claimed Novoplanski. Other advantages of the tire include a bigger footprint than pneumatic tires, better load distribution, greater traction, higher efficiency, increased safety and a smoother ride, he said.
Airless tire offering
Meanwhile, SciTech Industries of Boca Raton, Fla., has worked for years on a completely airless tire, and is very close to having it ready for commercial production, said Michael Moon, SciTech vice president of engineering.
The tire industry and the U.S. Army have long shown an interest in developing a functional airless tire, according to Moon, and made multiple attempts at inventing one.
“A urethane foam tire gained DOT approval, but a non-standard rim and wet traction problems doomed this technology,” he said.
Other tire producers have made airless urethane tires, but non-standard rims, high production costs and heavy road noise have prevented their being used on any vehicles other than the Segway transporter, he said.
SciTech bases its design on the work of Gyula Subotics, the former research and development head of the now-defunct Taurus tire company in Hungary, Moon said.
Ten years of development work has produced a radical, patented new tire design with supports made from a thermoplastic glass fiber composite never before used in the tire industry, he said.
A tire made from the SciTech design was molded at a contract tire factory in Eastern Europe and tested successfully, on a standard rim, at a lab in Ohio, according to Moon.
“The heart of the tire is the composite supports,” he said. “The challenge was to build supports that were strong enough.”
The SciTech tire tests well against existing pneumatic tire standards, according to Moon. SciTech's new nano-clay technology will improve flexural strength significantly with very little added cost, but otherwise the tire uses conventional rubber compounds.
“There are no expensive materials, no hidden surprises,” he said.
SciTech believes its tire will improve vehicle fuel economy by as much as 2 percent, thanks to less sidewall flex than pneumatic tires, according to Moon. The tire never runs hot, and the absence of air eliminates slow leaks, spare tires and tread separations caused by underinflation, he said.
The company also has successfully retreaded the airless tire, using both pre-cure and mold-cure technologies, Moon said.
“The lack of calendered belts and steel belts will give a great increase in carcass durability,” he said. “This tire may well bring passenger tires back to retreaders, which has not been the case for decades.”
Currently, SciTech is seeking a strategic partner to commercialize the tire, according to Moon. “All claims we have made, we are able to substantiate,” he said.
Michael R. Fraley, president and CEO of Arizona-based PanAridus L.L.C., has spent more than 20 years developing successful agribusiness companies.
However, a 2004 meeting with old guayuleros—agronomists who worked on government programs to extract commercial quantities of rubber from the desert shrub guayule during World War II and again in the 1980s—gave him the impetus to work on commercializing guayule himself, he said.
In 1910, guayule provided 50 percent of U.S. natural rubber needs and 10 percent of the world's, Fraley said. However, the only guayule plants grew wild, and the inability to cultivate them caused the guayule business to die out, he said.
The Emergency Rubber Project of World War II allocated $45 million for guayule development, but also $650 million for synthetic rubber development, according to Fraley.
“After the war, all information on guayule was classified, and all guayule fields disked under,” he said. “It took 30 years to access guayule documents through the Freedom of Information Act.”
In the 1980s, the Sacaton guayule project in Arizona, overseen by the Defense Department, Firestone and the Gila River Indian tribes, made some progress but fell apart after a fall in oil and natural rubber prices, Fraley said. But the aqueous extraction process for guayule latex developed in the 1990s by the U.S. Department of Agriculture revived interest in the shrub, he said.
PanAridus, whose new website will go live in mid-May, has the largest team of agronomists in the world and has developed the world's largest germplasm bank, Fraley said.
The company already has done substantial work in guayule, he said. “We extracted kilograms of guayule from our plants—the first time that's been done in 25 years,” he said. “The guayule rubber meets or exceeds all ASTM/ISO standards.”
However, the per-acre yield of guayule has to be increased to make the rubber viable on a global basis, Fraley said. “We are cognizant of receiving diminishing returns with conventional plant breeds,” he said. “But time is money, and we have the technology to grow rapidly.”