Burgess, Ryan and Wayne
Process for preparation of compositions of bitumen polymers and products
 A method of preparation of polymer-asphalt (bitumen) compositions which comprises mixing, with agitation, at a temperature of 130.degree. to 230.degree. C., 80 to 98% by weight of an asphalt having a penetration between 30 to 220, and 2 to 20% by weight of a polyblock copolymer of a styrene-carboxylated conjugated diene having a mean molecular weight of 30,000 to 300,000, and maintaining this mixture for at least 2 hours at this temperature, then adding 0.1 to 3% of elemental sulfur, based on the asphalt, while maintaining the same conditions of agitation and temperature for at least 20 minutes, the carboxylated conjugated diene sequence being selected from the group consisting of carboxylated polybutadiene and carboxylated polyisoprene. 
Elf France
C
C08L
inventional
Paul Trung Kiet Daniele
Maldonado Phung Eber