“Controlled” and “Living” Cationic Polymerizations:Another Way Towards Well Defined Polymer Architec

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1 Results No doubt that one of the major breakthroughs in polymer chemistry was the discovery and the progressive implementation of the “living” and “controlled” polymerizations.These now widely used techniques allow not only to control with an extreme precision the molar masses and their distributions but also to synthesise easily a broad variety of architectures from block and graft copolymers,miktoarms stars,to polymer brushes,hyperbranched polymers,dendrimers,etc....They opened an immense domain of new well defined polymeric materials with various specific properties and applications,and subsequently allowed major advances and understandings in polymer physics,mechanics,processing and material science in general.The “living” polymerization -chain polymerisation from which chain termination and irreversible chain transfer are absent-is an old story associated with the anionic polymerization and the stability of its (carb)anionic chain carriers,as well as with the outstanding pioneering work of Michael Szwarc and some others from the late 50’s.But the required purity of reagents and the complexity of the technical process limited the industrial development. 1 Results No doubt that one of the major breakthroughs in Polymer chemistry was the discovery and the progressive implementation of the “living” and “controlled” polymerizations. These now widely used techniques allow not only to control with an extreme precision the molar masses and their distributions but also to synthesise a broad variety of architectures from block and graft copolymers, miktoarms stars, to polymer brushes, hyperbranched polymers, dendrimers, etc .... They opened an immense domain of new well defined polymeric materials with various specific properties and applications, and subsequently allowed major advances and understandings in polymer physics, mechanics, processing and material science in general. “living ” polymerization -chain polymerisation from which chain termination and irreversible chain transfer are absent-is an old story associated with the anionic polymerization and the stability of its (carb) anionic chain carriers, as well as with the outstanding pioneering work of Michael Szwarc and some others from the late 50’s. But the required purity of reagents and the complexity of the technical process limited the industrial development.
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