Segmented and Gradient Copolymers Prepared by ATRP as Nanostructured Functional Materials

摘要

Atom transfer radical polymerization (ATRP) is among the most efficient controlled radical polymerization systems.1-4 Recent advances in understanding the mechanism of ATRP allowed to reduce amount of copper catalyst to ppm level,in the presence of various reducing agents.5-22 The amount of copper in the system can be correlated with the uniformity of of chains,i.e. polydispersity.23 ATRP provides an easy access to well-defined block,graft and gradient copolymers.24-31 These segmented and gradient copolymers prepared by ATRP can have linear but also more complex structure including star-block copolymers,miktoarm,cylindrical bottle brush,hairy particle and others.32-39 Various acrylates,methacrylates,acrylamides,acrylonitrile,styrene or vinyl pyridine have been successfully used as building blocks to prepare copolymers with controlled topology and composition. In addition,block copolymers were prepared by the mechanistic transformation procedures. In such a way cationic and anionic ring opening polymerizations,carbocationic and carbanionic polymerizations,coordination,metathesis,polycondensation or conventional radical polymerizations were successfully combined with ATRP40-52. In addition,ATRP was successfully united with other controlled radical polymerization techniques such as RAFT.