Mechanical and rheological properties of natural rubber compounds containing devulcanized ground tire rubber from several methods

In the recent past we reported the investigation of different devulcanization processes of a ground tire rubber (GTR) such as supercritical fluid, ultrasonic and biological technologies. Each of these techniques had been previously optimized, focusing on the experimental combination of parameters providing the best devulcanization conditions. The present study aims to extensively compare the optimal conditions of these three different techniques for the devulcanization of a GTR. In particular the GTR and the devulcanizates by each technique were blended into raw natural rubber at a concentration of 10 phr. The rheological and mechanical properties of their vulcanizates were investigated and compared to find out the rubber providing the highest compatibility for compounding and revulcanization. In addition, a comparison of these results was made with the ones of raw natural rubber compound and vulcanizate.