Polymer-bitumen primary mixtures that can be used for preparing polymer-bitumen binders, and products obtained from these primary mixtures

The aim of the invention is to provide, at a lower cost, novel primary mixtures that can be used for preparing polymer bitumens. For this purpose, the primary mixture according to the invention comprises: (a) at least 25 % by weight, preferably 25 to 80 % by weight, of polymer, (b) at least one thermoplastic tackifying resin having an average molecular mass of 100 to 3,000 g/mol, (c) and/or one or more mono-alkyl - preferably methyl - esters of fatty acids at C16-C18, in particular sunflower oil, linseed oil, rapeseed oil, soybean oil, and/or sunflower oil that is optionally isomerised; the ester (c) necessarily being present when the tackifying resin (b) has an acid value measured according to standard NF EN ISO 660 of less than 50 mg KOH/g. The invention also concerns the polymer bitumens, emulsions and coatings/coated products obtained from this primary mixture, as well as the methods for preparing same.