A study was carried out by Phoenix to evaluate the performance of Surface Activated and Regenerated (SAR) crumb rubbers in a rubber mix compared with a mix consisting of raw materials only.
For this study, truck tire treads were produced with these 2 types of rubber mixes. The tests were carried out over a period of one year in the context of daily trucking use, with progressive tire wear being measured by impartial drivers.
As the Phoenix rubber compound is a recipe in development, it has not been optimized, and its performance is necessarily slightly different from the properties of a commercial rubber mix, which is continually being improved.
A comparative wear analysis of Phoenix and commercial treads* showed that both types of rubber have very similar behaviours. According to the drivers, their wear rates and mechanical properties are identical. Moreover, from the measurements of tread block depth and correlating with mileage, all the statistical indicators showed that there is no non-standard variance, indicating, among other things, that the SAR had dispersed very well in the mix without affecting the expected mechanical performance.
A second Lidar measurement carried out by an external engineering firm, on a Phoenix tire and a commercial reference tire, confirmed that there was no significant difference*.
Although adding recycled rubber may reduce the physical properties measured in a laboratory, it does not proportionally affect the expected performance of the finished product. These results suggest the possibility of increasing the amount of SAR in the mix; for this test, 15% of the mass or 30 PHR was used. In the near future, up to 20% or more could be used, reducing mix costs and CO2 emissions.
It should also be noted that the SAR used was processed by our Generation Alpha crumb rubber processing equipment. The SAR we used also enabled us to confirm that, once processed, crumb rubbers can be used over two years after being processed, as long as they are kept protected from the elements and at a constant temperature, as is the case for any raw elastomer.
We are currently working on the Bravo Generation of our innovative technology. The improved Thermokinetic Mixer will provide a larger activated surface with less energy, while shortening crumb rubber processing cycles.
Pierre Bayeur,
* Technical documentation available upon signature of a confidentiality agreement.
