Ultrasmall 3D network morphologies from biobased sugar–terpenoid hybrid block co-oligomers in the bulk and the thin film states
Chaehun Lee,
Brian J. Ree,
Kai Chen,
Ryoya Komaki,
Satoshi Katsuhara,
Takuya Yamamoto,
Redouane Borsali,
Kenji Tajima,
Hsin-Lung Chen,
Toshifumi Satoh,
Takuya Isono
Affiliations
Chaehun Lee
Graduate School of Chemical Sciences and Engineering, Hokkaido University, Kita 13, Nishi 8, Kita-ku, Sapporo, Hokkaido 060-8628, Japan
Brian J. Ree
Department of Chemistry and Physics, Kean University, 1000 Morris Ave, Union, NJ 07083, United States
Kai Chen
Department of Chemical Engineering, National Tsing Hua University, Hsinchu 20013, Taiwan
Ryoya Komaki
Graduate School of Chemical Sciences and Engineering, Hokkaido University, Kita 13, Nishi 8, Kita-ku, Sapporo, Hokkaido 060-8628, Japan
Satoshi Katsuhara
Graduate School of Chemical Sciences and Engineering, Hokkaido University, Kita 13, Nishi 8, Kita-ku, Sapporo, Hokkaido 060-8628, Japan
Takuya Yamamoto
Faculty of Engineering, Hokkaido University, Kita 13, Nishi 8, Kita-ku, Sapporo, Hokkaido 060-8628, Japan
Redouane Borsali
University of Grenoble Alpes, CNRS, CERMAV, 38000 Grenoble, France
Kenji Tajima
Faculty of Engineering, Hokkaido University, Kita 13, Nishi 8, Kita-ku, Sapporo, Hokkaido 060-8628, Japan
Hsin-Lung Chen
Department of Chemical Engineering, National Tsing Hua University, Hsinchu 20013, Taiwan; Corresponding authors.
Toshifumi Satoh
Faculty of Engineering, Hokkaido University, Kita 13, Nishi 8, Kita-ku, Sapporo, Hokkaido 060-8628, Japan; List Sustainable Digital Transformation Catalyst Collaboration Research Platform, Institute for Chemical Reaction Design and Discovery, Hokkaido University, Kita 21, Nishi 10, Kita-ku, Sapporo, Hokkaido 001-0021, Japan; Corresponding authors.
Takuya Isono
Faculty of Engineering, Hokkaido University, Kita 13, Nishi 8, Kita-ku, Sapporo, Hokkaido 060-8628, Japan; Corresponding authors.
Nanoscale three-dimensional (3D) network morphologies, such as those represented by gyroids accessed by the self-assembly of block copolymers, are highly attractive platforms for the fabrication of nanostructured materials. However, it remains challenging to access such morphologies, especially in the sub-10 nm domain spacing region. Herein, we systematically investigated the microphase separation behaviors of biobased sugar–terpenoid hybrid block co-oligomers (BCOs) with different molecular parameters, including their volume fractions, the linker structures between the blocks, and the stereochemistries of the terpenoid blocks. The BCOs were synthesized using the azido–alkyne click reaction of propargyl-β-d-glucopyranoside with azido-functionalized farnesol, phytol, DL-α-tocopherol, and d-α-tocopherol, to ensure a well-defined molecular structure without any molecular weight distribution. Through X-ray scattering screening, we found that tocopherols, when combined with a glucose unit, yield BCOs capable of forming gyroid and hexagonally perforated lamellar (HPL) 3D network morphologies with ultrasmall domain spacings of ∼10 nm. Remarkably, HPL, which is known as a metastable phase in block copolymers, was obtained in both the bulk and film states. The nature of the linker structure and the stereochemistry of the tocopherol hydrocarbon chain were found to influence the resulting morphology and the long-range order of the nanostructures. We expect this study to contribute to the molecular design of precise block copolymers and the construction of intricate nanostructural templates with ultrasmall feature sizes.
