Design and synthesis of network-forming triblock copolymers using tapered block interfaces

We report a strategy for generating novel dual-tapered poly(isoprene-b- isoprene/styrene-b-styrene-b-styrene/methyl methacrylate-b-methyl methacrylate) [P(I-IS-S-SM-M)] triblock copolymers that combines anionic polymerization, atom transfer radical polymerization (ATRP), and Huisgen 1,3-dipolar cycloaddition click chemistry. The tapered interfaces between blocks were synthesized via a semibatch feed using programmable syringe pumps. This strategy allowed us to manipulate the transition region between copolymer blocks in triblock copolymers, providing control over the interfacial interactions in our nanoscale phase-separated materials independent of molecular weight and block constituents. Additionally, we show the ability to retain a desirous and complex multiply continuous network structure (alternating gyroid) in our dual-tapered triblock material.