A Method To Synthesize Multiblock Copolymers of Methyl Methacrylate and Styrene Regardless of Monomer Sequence

Multiblock copolymers of methyl methacrylate and styrene were created using atom transfer radical polymerization. The syntheses of poly(styrene-b-methyl methacrylate-b-styrene) (S-M-S) and poly(methyl methacrylate-b-styrene-b-methyl methacrylate) (M-S-M) triblock copolymers and poly(methyl methacrylate-b-styrene-b-methyl methacrylate-b-styrene-b-methyl methacrylate) (M-S-M-S-M) and poly(styrene-b-methyl methacrylate-b-styrene-b-methyl methacrylate-b-styrene) (S-M-S-M-S) pentablock copolymers are reported. This method is novel in that the resultant copolymers are very blocky in nature and yet can be synthesized regardless of the direction of cross-propagation; a styrene end can initiate the polymerization of methyl methacrylate, and methyl methacrylate ends can initiate the polymerization of styrene. This is contrary to anionic polymerization, which is commonly used to prepare block copolymers of styrene and methyl methacrylate. SEC analysis shows the kinetics of the homopolymerizations and the copolymerizations, while NMR analysis confirms the blocky nature of the copolymers.