MIXTURE OF BITUMEN, RUBBER POWER AND POLYMER, USED AS BINDER FOR ROAD

摘要

PROBLEM TO BE SOLVED: To obtain the subject mixture improved in storage stability by including bitumen, rubber powder, an α-olefin-unsaturated epoxide copolymer and specifying the Brookfield viscosity and softening point of the mixture. ;SOLUTION: This mixture comprises bitumen, 7-13 wt.% of rubber powder having a particle diameter of 0.01-1 mm, and 1-2 wt.% of the copolymer of an α-olefin with at least one kind of unsaturated epoxide, and has the following characteristics. A Brookfield viscosity measured on the basis of NFT standard 76102 (needle 27) at 180°C is ≤1,150 mPas. An absolute difference between softening points (ring/ball softening point) at both the head and bottom portions of the mixture after stored in a vertical tube at 180°C for three days is ≤5°C measured on the basis of NFT 66008. The ring/ball softening point of the mixture is higher by 13-20°C than that of the bitumen alone. The penetration of the mixture is improved by 15-35 points (1/10 mm) in comparison with that of the bitumen alone.;COPYRIGHT: (C)1999,JPO