Abstract: The invention relates to a novel polyphosphorus-based chain-end thiol-functionalized polymer, the polymer chain of which comprises units bearing at least one pendant phosphonate function and/or at least one pendant phosphonic function along the chain. This novel polymer is quite particularly suited to participating in a thiol-ene coupling reaction, which affords the possibility of grafting the polyphosphorus-based polymers onto diene polymers, for example.

Abstract: The invention relates to a method for the synthesis of a novel diene polymer with a high content of phosphorus-based functions by radical grafting of a polyphosphorus-based polymer bearing a chain-end thiol function onto a diene polymer according to the following steps: a) bringing together, with stirring, at least one diene polymer in solution and at least one polyphosphorus-based polymer bearing a chain-end thiol function in solution, b) heating the homogeneous reaction mixture obtained in the previous step to the grafting reaction temperature, and c) adding the radical initiator concomitantly with either of steps a) and b) or once the grafting reaction temperature has been reached.