Burgess, Ryan & Wayne
Process for preparing bitumen-polymer compositions, application of these compositions of the obtention of coverings and mother solution of polymer usable for the obtention of the said compositions
 Bitumen-polymer compositions are prepared, by mixing, at between 130.degree. C. and 230.degree. C., a bitumen with a styrene and conjugated diene copolymer and a sulphur source, the copolymer and the sulphur source being added to the bitumen either directly, or in the form of a mother solution in a hydrocarbon oil, then by maintaining the whole under stirring at between 130.degree. C. and 230.degree. C. for at least fifteen minutes. By way of sulphur source is used 0.005 to 15% by weight, with respect to bitumen, one or several polymeric or not, cyclic or linear polysulphides, and especially ditertiododecyl or dinonyl pentasulphide. The bitumen-polymer compositions obtained can be used for the obtention of superficial road coverings and present a constant quality of its properties. 
Societe Anonyme dite: Elf France
C C
C08L C10C
inventional inventional
Jacques Paul Germain
Maurice Maldonado Hagenbach