METHOD OF PRODUCING MODIFIED ROAD BITUMEN BASED ON POLYMER COMPOSITION Russian patent published in 2025 - IPC C08L95/00 C08J11/04 

FIELD: construction; chemistry.

SUBSTANCE: invention relates to road construction and specifically to the technology of producing polymer-bitumen binder, and can be used to prepare high-quality cast and hot asphalt mixes. Method of producing modified road bitumen involves mixing bitumen, a plasticising additive and a polymer modifier. Initial bitumen used is off-grade commercial-grade bitumen “БНД” 70/100, modified by adding 4% uniplast as a plasticising additive and 4% of a polymer composition consisting of wastes - pulverized polyethylene terephthalate, thermally unstable high-pressure polyethylene and off-grade polycaprolactone in ratio of 1:1:1. Polymer composition is obtained by melting polymers on a sand bath until their softening and mixing with each other at temperature of 220 °C, crushing produced and cooled mass to state of flex (flakes), extrusion of flakes to produce a filament (homogeneous thread) and crushing the filament to produce a granulate. Modified bitumen is obtained by mixing a plasticising additive and a polymer composition at temperature above 200 °C for 20 minutes, followed by mixing the resulting melt with bitumen at 150 °C for 30 minutes and settling at ambient temperature 20 ± 5 °C for at least 12 hours, with the following ratio of components, wt.%: bitumen 92, plasticising additive 4, polymer composition 4.

EFFECT: improved operational characteristics of the polymer-bitumen composition, as well as reduced environmental impact of plastic wastes owing to use of off-grade and waste polymer modifiers.

1 cl, 8 tbl, 6 ex