Vulcanization accelerators as alternative to elemental sulfur to produce storage stable SBS modified asphalts

•We studied the storage stability of SBS modified asphalts.•We tested ten vulcanization accelerators as stabilizing agent.•Out of the ten products, two gave performance comparable to sulfur.•The thermal stability of the additives seems to correlate with their efficiency.

Storage stability is one of the main problems of polymer modified asphalts and the use of elemental sulfur is probably the most effective solution, even if not free from inconveniences. Here ten commercially available vulcanization accelerators were tested as potential alternative to sulfur and added to asphalts modified with SBS. Mixing asphalt and polymer at 180 °C, out of the 10 products two gave performance comparable to sulfur, while some of the other additives became effective only at mixing temperature of 210 °C and a few did not work at all. A qualitative correlation between the thermal stability and the effectiveness of the additives was attempted through the thermogravimetric analysis.