Anionic to CRP

The anionic polymraization of butadiene (BD) with -butyl lithium to form Uving polybutadiene hthium can be taminated by reaction with a nitroxide, which can then be used to mediate a subsequent styrene polymerization, as shown. 

The ring-opening polymerization of e-caprolactone (ECL) using AlEtg in tribro-moethanol produces a Br-terminated poly(caprolactone), e.g., 

This can act as a macroinitiator that can be nsed to polymerize MMA, using a niekel bromide complex eatalyst (NiBrjlPPhjlj) thereby yielding a diblock copolymer (PECL-b-PMMA). 

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