Katsumata Research Group

Assistant Professor
Phone: 413-577-1121
Email: rkatsumata@umass.edu

Meet the Katsumata Group!

Degree Information:

B.Eng. Organic and Polymeric Materials, Tokyo Institute of Technology, 2009
M.Eng. Organic and Polymeric Materials, Tokyo Institute of Technology, 2011
Ph.D. Chemical Engineering, The University of Texas at Austin, 2016

Katsumata Group Website

Mailing Address:

Department of Polymer Science and Engineering
Room: A516, Conte Research Center
University of Massachusetts Amherst
120 Governors Drive
Amherst, MA 01003

Research Interests

Design Extremely Confined Soft/Hard Interfaces

Current Research

Katsumata Group’s research goal is to establish design rules of extremely confined soft/hard interfaces. Extremely confined interfaces become more critical for hybrid materials design at the intersection of two emerging research thrusts: precise synthesis of sequence-defined polymers and miniaturization of things. Examples in which such interfaces are prevalent include nanocomposites with ultra-small nanoparticles, ultra-thin polymer films/coatings, and two-dimensional (2D) materials with critical dimensions smaller than 10 nm. Despite emerging capabilities to synthesize these materials with precision, the influence of extreme confinement is not fully understood. The thermophysical properties of extremely confined molecules are often governed by rules different from those of bulk and moderately confined systems (> 10 nm scale). As the nanoparticle diameter and the coating thickness approach the size of polymer segments, molecular-level understanding becomes critical. In particular, my group focus on three areas: dynamics, mechanics, and wettability. Polymer dynamics is the foundation of my research program and involves elucidating molecular movements due to perturbations by neighboring molecules, introducing molecular-level heterogeneity. The heterogeneous polymer dynamics then dictates the tangible properties we can touch and feel: wettability and mechanics. Wettability is an incarnation of polymer dynamics, as molecules rearrange their configurations at interfaces. Analogously, mechanical properties are macroscopic responses of polymer dynamics on different length and time scales. Our approaches include fluorescence spectroscopy, rapid thermal annealing, and film-stress measurement in addition to conventional instrumentation and synthesis methods for polymer science and engineering.

Recent Publications

“Polymer Zwitterions as “Electronic Tuning of Monolayer Graphene with Polymeric “Zwitterists”,” J.N. Pagaduan, N. Hight-Huf, A. Datar, M. Barnes, D. Naveh, A. Ramasubramaniam*, R. Katsumata*, and T. Emrick*, accepted to ACS Nano, 2021.

“Glass Transition and Self-Diffusion of Unentangled Polymer Melts Nanoconfined by Different Interfaces” Reika Katsumata, Austin R. Dulaney, Chae Bin Kim, and Christopher J. Ellison, Macromolecules, 2018, 51 (19), 7509-7517

“Mussel-Inspired Strategy for Stabilizing Ultrathin Polymer Films and Its Application to Spin-On Doping of Semiconductors” Reika Katsumata, Ratchana Limary, Yuanyi Zhang, Bhooshan C. Popere, Andrew T. Heitsch, Mingqi Li, Peter Trefonas, and Rachel A. Segalman, Chemistry of Materials, 2018, 30 (15), 5285-5292

“Large area Fabrication of Graphene Nanoribbons by Wetting Transparency-assisted Block Copolymer Lithography” Reika Katsumata, Maruthi Nagavalli Yogeesh, Helen Wong, Sunshine X Zhou, Stephen M Sirard, Tao Huang, Richard D Piner, Zilong Wu, Wei Li, Alvin L Lee, Matthew C Carlson, Michael J Maher, Deji Akinwande, Christopher J Ellison, Polymer, 2017, 110, 131-138

“Conflicting Confinement Effects on the Tg, Diffusivity, and Effective Viscosity of Polymer Films: A Case Study with Poly(isobutyl methacrylate) on Silica and Possible Resolution” Kun Geng, Reika Katsumata, Xuanji Yu, Heonjoo Ha, Austin R Dulaney, Christopher J Ellison, Ophelia KC Tsui, Macromolecules, 2017, 50 (2), 609-617

Honors and Distinctions

  • National Science Foundation: NSF CAREER (2021)
  • American Chemical Society, Petroleum Research Fund, Doctoral New Investigator Grant (2019)
  • Robert H. DeWolfe Teaching Fellowship in Organic Chemistry, The Department of Chemistry and Biochemistry UCSB (2018)
  • Takenaka Scholarship Foundation, International Study Fellowship (2012-2016)