FIELD: chemistry.
SUBSTANCE: invention essentially relates to bitumen compositions and methods for production thereof. Composition contains: basic bitumen in an amount of about 91 to about 96 wt. % based on the total weight of said composition, selected from efficiency classes PG 58-28, PG 64-22, PG 52-34 and combinations thereof; non-epoxidised oil selected from semi-slugs, corn oil and combinations thereof in an amount of about 2.5 to about 6 wt. % based on the total weight of said composition to increase resistance to thermal cracking; and at least one polyolefin in a total amount of about 1.2 to about 3 wt. % based on the total weight of said composition to increase resistance to deformation. Polyolefin is a low-density polyethylene homopolymer having a weight-average molecular weight (Mw) of about 5,000 to about 7,000 g/mol and a density of about 0.92 to about 0.94 g/cm3, or the polyolefin is an oxidised high-density polyolefin having a weight-average molecular weight (Mw) of about 12,000 g/mol, acid number from about 24 to about 27 mg KOH/g and density from about 0.97 to about 1.0 g/cm3. Also, the composition can optionally include about 0.8 wt. % maleated polypropylene, based on the total weight of said composition, wherein said maleated polypropylene has weight-average molecular weight (Mw) from about 7,000 to about 11,000 g/mol, saponification number from about 75 to about 95 mg KOH/g and density from about 0.92 to about 0.94 g/cm3. Besides, composition has efficiency class PG from 58.1 to 66.6 and from −28.8 to −37.6, where characteristic from 58.1 to 66.6 represents average maximum design temperature of road surface for seven days in degrees Celsius and represents resistance to deformation, and the characteristic from −28.8 to −37.6 is the average minimum design temperature of the road surface for one day in degrees Celsius and represents resistance to thermal cracking, wherein each said value is determined in accordance with M320 AASHTO.
EFFECT: improved high-temperature and low-temperature characteristics of bitumen compositions.
6 cl, 1 tbl, 12 ex
