Recycled thermoplastics modified bitumen improved with thermoplastic elastomer

The use of different types of recycled plastic waste such as recycled polypropylene (PP), recycled low-density polyethylene (LDPE) and recycled polystyrene (PS), as raw materials for bitumen modification is known. However, the mechanical and thermal properties of recycled plastic waste modified bitumen (RPMB) are lower than those of the pure plastic modified bitumen. Therefor this paper aims to study the mechanical and thermal properties improvement of the RPMB with the use of a commercial elastomer styrene-butadiene-styrene (SBS). Initially conventional 35/50 quality bitumen was mixed with different percentages of LDPE, PS and PP, and then doped with commercial SBS. Basic rheological parameters such as penetration, softening point, elastic recovery and penetration index showed the changes caused by each rate of polymer addition to pure bitumen. The tests showed that the penetrability of the modified bitumen decreases and its softening point and elastic recovery increases, resulting in a decrease in the thermal sensitivity of the new bitumen mixture.