RUBBER-POLYMER-BITUMEN BINDER AND METHOD FOR PRODUCTION THEREOF Russian patent published in 2021 - IPC C08L95/00 C08J3/20 C08K9/00 C08K5/00 C08J11/00 

FIELD: road building.

SUBSTANCE: invention relates to road building materials, particularly, to composite binder compositions based on organic compounds for preparation of asphalt-concrete mixtures used in construction and repair of roads, bridges and airfields, namely to a rubber-polymer-bitumen binder and to methods for production thereof. Proposed is a binder based on bitumen, organic plasticiser, polymer from the divinylstyrene thermoplastic elastomer group, and rubber powder. A heavy vacuum gas oil is used therein as an organic plasticiser, a devulcanised rubber powder with an average size of agglomerated particles of less than 0.31 mm and a specific surface area of 0.3 to 0.8 m²/g is used as a rubber powder, and additionally used is a surface-active agent with active maleic groups at the following ratio of the named ingredients, % wt.: at least one polymer from the divinylstyrene thermoplastic elastomer group 2.8 to 6.1, heavy vacuum gas oil 8.5 to 13.1, devulcanised rubber powder 9.8 to 13.9, surface-active agent with active maleic groups 0.7 to 1.1, bitumen the rest. The method includes introducing a plasticiser, rubber powder, polymer from the divinylstyrene thermoplastic elastomer group, into bitumen. The named ingredients are therein introduced into the bitumen sequentially and discretely in a mode of continuous forced mass transfer and maintaining the temperature of the reaction mass not above 145°C, and each subsequent ingredient is introduced into a reaction mass with homogeneity achieved by said mass transfer, wherein after the polymer from the divinylstyrene thermoplastic elastomer group is introduced, the surface-active agent with active maleic groups is additionally introduced into the reaction mass, or a previously formed homogeneous solution of the polymer from the divinylstyrene thermoplastic elastomer group is first introduced into the bitumen in the heavy vacuum gas oil, then into the formed reaction mass with homogeneity achieved by said mass transfer, introduced sequentially and discretely is the surface-active agent with active maleic groups, then the devulcanised rubber powder.

EFFECT: production of a rubber-polymer-bitumen binder with increased values of softening temperatures and low brittleness temperatures, as well as with increased fatigue life, maintained both in severe cold and hot climatic conditions under high mechanical stress.

16 cl, 3 ex