POS1-1185
Library Synthesis of Methacrylate-Styrene Alternating Copolymers Using a Highly Side-Chain Transformable Monomer and Their Sequence-Specific Properties
When and Where
Nov 30, -0001
12:00am - 12:00am
Presenter(s)
Haruto Nitanda (Graduate School of Engineering, Kyoto University)
Co-Author(s)
Abstract
Sequence-controlled copolymers are expected to exhibit sequence-specific properties arising from their periodic and uniform sequence, which are distinct from those of conventional statistical copolymers. Although radical copolymerization is one of most versatile methods for polymer synthesis because of its broad monomer scope, the preparation of structurally diverse sequence-controlled copolymers remains challenging. We have recently developed a methacrylamide monomer carrying saccharin pendant that undergoes alternating copolymerization with styrene. The resulting copolymer can be transformed into methacrylate–styrene alternating copolymers via alcoholysis. However, the scope of side-chain transformation has been limited to primary and secondary alcohols, restricting the accessible alternating copolymers and the sequence-specific properties.
In this work, we designed a new transformable methacrylamide monomer that retains alternating copolymerizability while exhibiting enhanced side-chain transformability for alcoholysis. Twisted amide structures are known to exhibit reduced amide resonance stabilization, thereby increasing the reactivity toward nucleophilic substitution. Based on this concept, we designed a new monomer, and density functional theory (DFT) calculations revealed twisted amide conformation, suggesting enhanced alcoholysis reactivity. Consequently, methacrylate–styrene alternating copolymers bearing a wide variety of bulky and fluorinated side chains were successfully synthesized.
The resulting copolymers exhibit sequence-dependent properties that were distinct from those of the corresponding statistical copolymers. In particular, the glass transition temperatures were significantly lower than those of the corresponding statistical copolymers. Furthermore, sequence-controlled block copolymers composed of two alternating copolymer segments were successfully synthesized and were found to undergo microphase separation.
In this work, we designed a new transformable methacrylamide monomer that retains alternating copolymerizability while exhibiting enhanced side-chain transformability for alcoholysis. Twisted amide structures are known to exhibit reduced amide resonance stabilization, thereby increasing the reactivity toward nucleophilic substitution. Based on this concept, we designed a new monomer, and density functional theory (DFT) calculations revealed twisted amide conformation, suggesting enhanced alcoholysis reactivity. Consequently, methacrylate–styrene alternating copolymers bearing a wide variety of bulky and fluorinated side chains were successfully synthesized.
The resulting copolymers exhibit sequence-dependent properties that were distinct from those of the corresponding statistical copolymers. In particular, the glass transition temperatures were significantly lower than those of the corresponding statistical copolymers. Furthermore, sequence-controlled block copolymers composed of two alternating copolymer segments were successfully synthesized and were found to undergo microphase separation.
