PJ ZEON Award for outstanding papers in Polymer Journal 2025

Masayuki Gon received a Ph.D. degree from Kyoto University (Prof. Yoshiki Chujo group) in 2016. He worked as a visiting research fellow at Virginia Commonwealth University in America (Prof. Kenneth J. Wynne group) in 2014. Next, he became an assistant professor at Kyoto University (Prof. Yoshiki Chujo group) in 2016, and now he is an assistant professor at the same institute (Prof. Kazuo Tanaka group) since 2018. His research interest is functional π-conjugated materials featuring heteroatoms.

About the award article: the authors reported that π-conjugated polymers containing hypervalent tin(IV) units can be applied to organic NIR scintillators. The polymers showed efficient NIR emission both in solution (absolute photoluminescence quantum yield: ΦPL ~ 26%) and film (ΦPL ~ 2%) owing to the hypervalent state of tin(IV) and the expanded π-conjugated system. In practical use, the radioluminescence showed good linearity across the dose rate in the range from 50 to 5000 mGy h⁻¹. The findings propose that the NIR emitters containing heavy elements are a promising platform for creating novel organic NIR scintillators.

Atsushi Matsumoto received his Ph.D. in Macromolecular Science from Osaka University in 2017. After working as a postdoctoral scholar at the Okinawa Institute of Science and Technology (Micro/Bio/Nanofluidics Unit), he joined the University of Fukui in 2021, where he is currently a Senior Assistant Professor in the Department of Applied Chemistry and Biotechnology. His research interests focus on polymer physics and rheology, particularly the dynamics of charged polymer systems and soft materials.

About the award article: The author investigated the entanglement dynamics of salt-free polyelectrolyte solutions in the semidilute regime using a combination of conventional bulk rheology and diffusing wave spectroscopy (DWS) microrheology. This approach enabled access to high-frequency viscoelastic responses that are typically difficult to measure with standard rheometers. Through this methodology, key entanglement parameters, such as the entanglement concentration, plateau modulus, reptation time, and Rouse time of an entanglement strand, were quantitatively determined. The results revealed a crossover from polyelectrolyte-like to neutral polymer-like behavior, providing experimental support for predictions of the Dobrynin scaling model and resolving previous inconsistencies in the literature reports.

Akira Takahashi received a Ph.D. in 2017 from Tokyo Institute of Technology under the supervision of Prof. Hideyuki Otsuka. He was a JSPS research fellow (DC2) in 2017. He started his academic career as an Assistant Professor at Kanagawa University in the group of Prof. Atsushi Kameyama in 2017, and then moved to Tokyo Institute of Technology (currently Institute of Science Tokyo) in 2023. His research interests focus on polymer materials with modulable structures and properties.

About the award article: This paper presents a simple yet powerful method to control polymer chain mobility based on a boratrane structure, which has a cage structure that can be selectively opened to form flexible triethanolamine and reversibly reclosed through a chemoselective boration. By incorporating boratrane units into the polymer side chains, the structural conversion induces exceptionally large, reversible mobility changes, with Tg shifts up to 166 °C. Supported by systematic experiments and computations, this study establishes a versatile platform for polymers with dynamically tunable properties.

Yusuke Yasuda received his Ph.D. from the University of Tokyo under the supervision of Professor Kohzo Ito in 2020. During his doctoral course, he was selected as a JSPS DC2 research fellow. He joined Dr. Hiroshi Morita’s group at AIST (2021–2024), and Assoc. Prof. Kazushi Fujimoto’s group at Kansai University (2024–2025). In 2025, he joined Prof. Tsuyohito Ito’s group at the University of Tokyo as an assistant professor. His research interests are structure–dynamics–property relationships in cross-linked rubbers and gels.

About the award article: The authors investigated network reformation in dissociative dynamic bond elastomers using coarse-grained MD. These elastomers initially form kinetically controlled network structures and evolve into thermodynamically annealed structures through bond exchange. Although the total cross-link density remains unchanged, annealing decreases the fraction of interchain cross-links, leading to a reduction in the elastic modulus, the extent of which depends on the one-dimensional sequence of binding sites. These findings provide insights into the network reformation mechanism of dynamic bond elastomers and guidelines for designing of dynamically crosslinked materials.