Abstract
Molecular dynamics simulations are used to study binary blends of an AB-type diblock and an AB2-type miktoarm triblock amphiphiles (also known as high-χ block oligomers) consisting of sugar-based (A) and hydrocarbon (B) blocks. In their pure form, the AB diblock and AB2 triblock amphiphiles self-assemble into ordered lamellar (LAM) and cylindrical (CYL) structures, respectively. At intermediate compositions, however, the AB2-rich blend (0.2 ≤ xAB ≤ 0.4) forms a double gyroid (DG) network, whereas perforated lamellae (PL) are observed in the AB-rich blend (0.5 ≤ xAB ≤ 0.8). All of the ordered mesophases present domain pitches under 3 nm, with 1 nm feature sizes for the polar domains. Structural analyses reveal that the nonuniform interfacial curvatures of DG and PL structures are supported by local composition variations of the LAM- and CYL-forming amphiphiles. Self-consistent mean field theory calculations for blends of related AB and AB2 block polymers also show the DG network at intermediate compositions, when A is the minority block, but PL is not stable. This work provides molecular-level insights into how blending of shape-filling molecular architectures enables network phase formation with extremely small feature sizes over a wide composition range.
Original language | English (US) |
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Pages (from-to) | 1405-1416 |
Number of pages | 12 |
Journal | JACS Au |
Volume | 2 |
Issue number | 6 |
DOIs | |
State | Published - Jun 27 2022 |
Bibliographical note
Funding Information:This work was supported by the National Science Foundation through the University of Minnesota MRSEC under Award DMR-2011401. Computer resources were provided by this NSF award and by the Minnesota Supercomputing Institute. Z.Y.S. acknowledges support through the Richard D. Amelar and Arthur S. Lodge Fellowship.
Publisher Copyright:
© 2022 The Authors. Published by American Chemical Society.
Keywords
- Amphiphile Phase Behavior
- Continuous Network Phases
- Molecular Modeling and Simulation
- Polymer Blends
- Self-Consistent Field Theory
PubMed: MeSH publication types
- Journal Article