The bitumen / polymer composition having a very low thermal susceptibility, for its preparation and application of this composition is in the embodiment of coatings.

摘要

The bitumen/polymer composition exhibits a penetration of between 80 and 400 and a ring-and-ball softening temperature higher than 55 DEG C and these are such that the Pfeiffer value, connecting these quantities, is higher than 5. This composition is obtained (i) by forming a bitumen/polymer component by bringing a hydrocarbon fraction of kinematic viscosity at 100 DEG C of between 0.5 x 10-4 m2/s and 3 x 10-4 m2/s into contact with 5 to 25 %, by weight of the said fraction, of a sulphur-crosslinkable elastomer in the presence of an effective quantity of a sulphur-donating coupling agent, the operation being carried out with stirring between 100 DEG C and 230 DEG C, and then (ii) by mixing the bitumen/polymer component with a quantity of a bitumen with a penetration of between 10 and 100, such as to produce a final composition containing 0.5 to 15 % by weight of vulcanised elastomer. The bitumen/polymer composition can be employed for the production of road dressings, coated mixes or other sealing coatings.