| 摘要 |
Stabilising pitch-bitumen blends, which can be softened with tar oils, includes mixing coal tar pitch, before petroleum bitumen is added, with aromatic hydrocarbon resins of the indene type or with technical prods. contg. these resins. The coal tar pitch has softening pt. (ring and ball) 40-120 deg.C. The bitumen component pref. has penetration 40-120 x 0.1 mm and may be an extn. bitumen, as well as the distn. bitumens usually used in road building. The hydrocarbon resin is pref. a cumarone -indene resin, including one of the dark types; or it may be one obtd. from the pyrolysis residues from ethylene prodn. from gasoline.
|
