Retarded anionic polymerization (RAP) of styrene and dienes

The possibilities to achieve a quantitative living-like anionic polymerization of styrene and dienes in the absence of solvent and at elevated temperature and using inexpensive initiating systems were explored to make the anionic polymerization competitive with industrial radical processes and allow the industrial production of anionic polystyrene (PS). It implied at first to control the reactivity and stability of initiating and propagating active species in such unusual operating conditions. To achieve these goals the so-called styrene and butadiene “Retarded Anionic Polymerization” (RAP) have been developed. This review focuses on the description of different bimetallic anionic polymerization systems which are able to approach or fulfill the industrial conditions for styrene and dienes anionic polymerizations.