Effect of Halogen Chain End Fidelity on the Synthesis of Poly(methyl methacrylate-b-styrene) by ATRP

Poly(methyl methacrylate-b-styrene)(PMMA-b-PS) block copolymers are synthesized by two consecutive ATRPs and fractionated into four fractions. The halogen chain end fidelity(CEF) in PMMA-b-PS is quantified based on the analysis of each fraction. Compared to ethyl 2-phenyl-2-bromoacetate/CuBr/2,2′-bipyridine(EPBA/CuBr/bpy) and CuBr/N,N,N′,N′′,N′′-pentamethyldiethylene-triamine(CuBr/PMDETA) catalysts, PMMA-b-PS synthesized using p-toluenesulfonyl chloride/CuCl/bpy(TsCl/CuCl/bpy) and CuCl/PMDETA catalysts has a higher halogen CEF and a better control on molecular weight.