Cationic to CRP

The carbocationic polymerization of styrene using SnCl4 results in Cl-terminated PS ehains. These ean be isolated, purified, and in the presenee of a eopper eatalyst such as CuQ/(dNbpy)2, fiulher polymerization of MA or MMA can be initiated to form diblock copolymers with polydispersities of 1.2 and 1.6, respectively. 

A transformation from cationic ring-opening polymerization (CROP) to ATRP, or vice versa, can also be effected, as shown below. 

the cationic ring-opening polymerization of tetrahydrofuran (THF) using silver triflate (AgOTf) in the presence of 2-bromopropionylbromide produces a Br-terminated PTHF. Block copolymers can then be prepared using S, MMA, and MA, employing a CuBr/(dNbpy)2 catalyst. 

ABA triblocks can be prepared by forming a bifunctional PTHF, which is then 

Further reaction with styrene produces triblock ABA copolymers. 

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