MINNEAPOLIS—The rubber industry's drive toward sustainability and green technology is drawing favorable attention to NorthStar Elastomers L.L.C.'s patented Tirecycle technology, according to executives of the Minneapolis-based company.
"There's a lot more activity surrounding Tirecycle," said Jim Judson, director of sales for NorthStar. "The attractiveness of recycled materials has grown a lot recently, but especially in Europe, where the emphasis on green manufacturing and sustainability is driven by regulations within the European Union."
Tire and rubber product manufacturers in Europe and elsewhere are expressing interest in Tirecycle, not just as a way to use recycled rubber, but also as a superior technology that enhances the performance of rubber products when blended with virgin rubber, according to Judson.
"They're looking at it as upcycling, rather than simply recycling," he said.
The green manufacturing factor is important to the future of Tirecycle, according to NorthStar President Terry Korupp. In recent years, the low prices of virgin rubber have made it difficult for recycled materials to compete on price alone.
"You can make a beautiful product, but your clientele doesn't necessarily want to spend an extra 50 cents," Korupp said.
According to the NorthStar website, Tirecycle has a long list of applications, including tire treads, shoe soles, hoses, grommets, conveyor belting, rubber sheets, mining and automotive components, agricultural equipment, waterproofing and roofing.
Tirecycle has been tested and used in standard tread compounds for most types of truck, passenger and off-the-road tires for more than 30 years, according to NorthStar's summary of support data on the material.
It is a fully reactive crumb rubber compound derived from high-specification cured tread rubber that blends readily into NR/SBR/BR base masterbatches and cures identically, the company said.
According to Judson, Tirecycle can be blended into virgin rubber at levels from 25 to 87.5 percent. NorthStar claims benefits from the use of Tirecycle including:
- A 15 percent increase or greater in tread life when used at a 50-50 ratio;
- A reduction in rolling resistance, showing up as higher MPG and lower heat gain;
- Improved safety;
- No rejects from blisters;
- A measurable increase in both wet and dry traction; and
- A reduction of as much as 30 percent in curing time, along with lower curing temperatures.
NorthStar also is getting encouraging results in its tests with graphene, an atom-thin carbon material that is 200 times stronger than steel.
Various studies have shown that graphene improves both the durability and traction of tires, according to Korupp. And NorthStar's own studies show that Tirecycle and graphene are very compatible, he said.
"We're looking at whether we should put graphene in our own mix, or if we should just look at the rubber that comes to us down the road," Korupp said. "A lot of it will be certain to contain graphene."
NorthStar Elastomers began life as Rubber Research Elastomerics in Minneapolis in the mid-1960s, as a producer of custom polymers mainly for the adhesive and sealant market.
At its peak in the 1980s, according to Judson, Rubber Research Elastomerics had 250 customers worldwide, including Australia and Europe.
"We sold 3 million shoe soles to Reebok in the mid-80s," he said. "A number of tire companies also used our product on taxi fleets."
Tirecycle technology grew out of Rubber Research Elastomerics' custom polymers business, according to Judson. Unfortunately, the company eventually went into decline.
"The owner kept too many things close to the vest," Judson said. "There was some corruption involved."
Minnesota Elastomers purchased the company in 2012. Not long afterward, according to Judson, a group of investors including Korupp bought the firm.
"Now Terry is running the show," Judson said.
NorthStar has a 20,000-sq.-ft. facility and can handle batches ranging from 500 to 10,000 pounds, depending on the type of mixer the material takes, Korupp said.
While Tirecycle has a long list of potential uses, it is best suited to those applications that require durability, such as tire treads, shoe soles, hoses and conveyor belts, according to Korupp.
"A grommet doesn't have the same kind of wear factor as a shoe sole or a tire," he said.
It will be some time before NorthStar can announce any new contracts, despite the increased interest from companies interested in green manufacturing, according to Judson.
"It takes six months to two years to get a sale," he said.
Nevertheless, NorthStar's future looks brighter than at any time in the past several years, according to Judson and Korupp.
"Tirecycle is a valid technology, and it's now a matter of getting it out there," Judson said.
Added Korupp: "I got control of the company at a time when everything tanked. Now, we're getting a lot better response, because our products do some things better, and we're happy to work with our customers."