Design of Gradient Copolymer Platform toward Advanced Optical Applications

Abstract

Research has been continuously conducted to achieve sequence-controlled polymers through various methods, with the goal of synthesizing perfect sequence-controlled materials such as DNA and proteins. In particular, gradient structures exhibit unique properties depending on the gradual changes in monomer composition in the polymer chain. By utilizing the differences in monomer reactivity ratios, copolymers with gradient structures can be synthesized. One example is cyclic olefin copolymers (COCs) synthesized using vinyl-addition polymerization. COCs can be polymerized using cyclic olefin monomers, with many cases involving norbornene (NB), which has a bicyclic structure. COCs synthesized through addition-type polymerization can maintain their bicyclic structure after polymerization. This results in key characteristics such as high transmittance, high thermal stability, and low birefringence. In this study, polymerization was carried out with NB-based monomers and methyl vinyl ketone (MVK) as the polar olefin monomer. Additionally, post-polymerization modification can be conducted in the ketone group in MVK within the polymers, allowing the polymers to be tailored for use in various fields and demonstrating their potential as upcyclable and recyclable materials.