Recent Aspects of Green Atom Transfer Radical Polymerization System with Low Catalyst Concentrations(abstract)

摘要

Atom transfer radical polymerization(ATRP)has emerged as one of the most powerful controlled/living radical polymerization yielding well defined(co)polymers,nanocomposites and biopolymers.ATRP has already been employed in industry and it can be expected that in near future it will emerge as a viable industrial process for the large scale production of speciality chemicals.The current awareness on ATRP is to develop active catalyst systems that can be used at low concentrations or at ambient temperatures while maintaining the sufficiently high reaction rates.Recently,two versatile new methods namely activator regenerated by electron transfer(ARGET)and initiators for continuous activator regeneration(ICAR)ATRP were developed for the activation of the catalyst complex by a reducing agent which does not form radicals capable of initiation.These methods provide a continuous controlled polymerization with a significant reduction of the amount of transition metal catalyst(down to ~ 10 ppm)due to constant regeneration of the activator species by environmentally acceptable reducing agents and radical initiators,which compensate for any loss of the catalyst by termination.