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Updated: Sep 22, 2025
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Synthesis of Monodisperse Cylindrical Nanoparticles via Crystallization-driven Self-assembly of Biodegradable Block Copolymers
Published on: June 20, 2019
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Formation of Tetragonally-Packed Rectangular Cylinders from ABC Block Terpolymer Blends
Yusuke Asai1, Kotaro Yamada1, Mutsuhiko Yamada1
1Department of Applied Chemistry, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan.
ACS Macro Letters
|May 20, 2022
Summary
Varying the composition distribution in poly(isoprene-b-styrene-b-2-vinylpyridine) triblock terpolymers shifts structures from gyroid to rectangular cylinders. This change is attributed to polymer chain localization at domain interfaces.
Area of Science:
- Polymer Science
- Materials Science
- Nanotechnology
Background:
- Block copolymers self-assemble into ordered nanostructures.
- Controlling these structures is key for advanced materials.
- Composition distribution influences self-assembly behavior.
Purpose of the Study:
- Investigate how composition distribution in ABC linear terpolymers affects periodic structure formation.
- Explore the transition from gyroid to cylindrical structures.
- Understand the role of polymer chain localization.
Main Methods:
- Synthesis of five poly(isoprene-b-styrene-b-2-vinylpyridine) (ISP) triblock terpolymers.
- Variable blending of terpolymers with controlled molecular weights and center-block fractions.
- 3D-Transmission Electron Microscopy (3D-TEM) observation of binary mixtures.
Main Results:
- Increasing composition distribution transforms tricontinuous gyroid structures into cylindrical structures.
- Rectangular cylinders packed tetragonally were observed with increased distribution.
- 3D-TEM confirmed more evident rectangular cylinders with 4-fold symmetry in specific mixtures.
Conclusions:
- Composition distribution is a critical factor in directing self-assembly of ABC terpolymers.
- A novel rectangular cylinder structure with nonconstant mean curvature was identified.
- Systematic localization of polymer chains at domain interfaces drives the formation of these unique structures.
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