Akiyuki Ryoki

I conduct microscopic-level structural analyses of polymer solutions using various scattering techniques, including visible light, X-rays, and neutrons. I am also involved in developing and refining these analytical methods.
Recently, I developed an empirical formula to describe the scattering function of linear polymer chains in good solvents. To validate the formula, I measured the scattering functions of several polystyrene samples with different molecular weights in various solvents. The results showed good agreement with the values predicted by the formula. This advancement allows us to analyze scattering functions of polymers at arbitrary excluded volume strengths, which was previously difficult to achieve.
In collaboration with researchers outside our laboratory, I have conducted structural analyses of various polymer systems. These include star polymers with helical arms, star polymers synthesized via the core-gel method, complexes of cyclic polymers with nanoparticles, and micellar aggregates formed by polymers in solution.
Current polymer physics is based on coarse-grained models, which have been quite successful. However, a major challenge is the lack of clear connections between the parameters that define these models and the actual chemical structures of the molecules they represent. I aim to address this issue by establishing a molecular-level understanding that bridges low- and high-molecular-weight systems and provides a comprehensive "molecular physics" of polymers.