Insights
Our experts share their thoughts on asphalt sustainability, innovation, safety and creating a culture of care.
Our experts share their thoughts on asphalt sustainability, innovation, safety and creating a culture of care.
Independent Studies Prove that SigmaBond Results in Upcycled Performance
Focusing on what’s possible is at the core of everything Polyco does. One of the innovations we are most excited about is the technology we’ve developed to reduce landfill waste by recycling waste tires. While there are many ways to recycle tires, Polyco’s patented Rapid Digestion Process (RDP) completely liquefies tire rubber so that it actually improves the performance of the paving bitumen. But don’t just take my word for it!
RDP is the “secret sauce” that powers our revolutionary asphalt modifier, SigmaBond. Two independent studies conducted at the National Center for Asphalt Technology (NCAT) at Auburn University and the University of Nevada, Reno prove that SigmaBond significantly improves fatigue resistance and thermal stability. Ultimately, these features lead to roads that last longer compared to those made with conventional materials.
The NCAT study analyzed several mix designs and evaluated the performance of each one after adding SigmaBond with 20% tire rubber to the mix. The results speak for themselves.
The two formulas with SigmaBond (labeled 82-22SR and 88-22HP) performed better in every category compared to NCAT’s control and unmodified mix design. In fact, the SigmaBond formulation that contained a higher percentage of SBS polymer (88-22HP) actually performed the best — with more than 300 times the fatigue resistance of conventional asphalt.
In the University of Nevada, Reno study, researchers evaluated the crack resistance of tire rubber-modified asphalt mixtures, including SigmaBond. The data shows both SigmaBond samples (PG70-16R and PG70-28TR) with 10% tire rubber significantly increased cycles to fatigue when compared to the PG70-10 conventional asphalt pavement with no tire rubber.
Additionally, the use of SigmaBond was correlated with an overall reduction in fatigue resistance. This performance improvement resulted in a 10% to 25% reduction in construction cost per lane-kilometer when compared to conventional asphalt pavement.
As these studies indicate, SigmaBond outperforms standard paving grade asphalt — enabling hot mix contractors to use more upcycled materials while extending the life of pavements and lowering costs.
The positive impacts on the environment are twofold; not only does Polyco provide a solution to the tire waste stream, but we also develop materials that create more sustainable roads for generations to come.