Reevaluation of Poly(ethylene-alt-propylene)-block-Polydimethylsiloxane Phase Behavior Uncovers Topological Close-Packing and Epitaxial Quasicrystal Growth

Aaron P. Lindsay, Ashish Jayaraman, Austin J Peterson, Andreas J Mueller, Steven Weigand, Kristoffer Almdal, Mahesh K Mahanthappa, Timothy P Lodge, Frank S Bates*

*Corresponding author for this work

Research output: Contribution to journalJournal articleResearchpeer-review

89 Downloads (Pure)

Abstract

Reanalysis of an asymmetric poly(ethylene-alt-propylene)-block-polydimethylsiloxane (PEP-PDMS) diblock copolymer first investigated in 1999 has revealed a rich phase behavior including a dodecagonal quasicrystal (DDQC), a Frank-Kasper σ phase, and a body-centered cubic (BCC) packing at high temperature adjacent to the disordered state. On subjecting the sample to large amplitude oscillatory shear well below the σ-BCC order-order transition temperature (TOOT), small-angle X-ray scattering evidenced the emergence of a twinned BCC phase that, on heating, underwent a phase transition to an unusually anisotropic DDQC state. Surprisingly, we observe no evidence of this apparent epitaxy on heating or cooling through the equilibrium σ-BCC transition. We rationalize these results in terms of a shear-induced order-order transition and an apparent BCC-DDQC epitaxy favored by micelle translation-mediated ordering dynamics far below TOOT.
Original languageEnglish
JournalACS Nano
Volume15
Issue number6
Pages (from-to)9453-9468
Number of pages16
ISSN1936-0851
DOIs
Publication statusPublished - 2021

Keywords

  • Lattices
  • Annealing (metallurgy)
  • Epitaxy
  • Phase transitions
  • Scattering

Fingerprint

Dive into the research topics of 'Reevaluation of Poly(ethylene-alt-propylene)-block-Polydimethylsiloxane Phase Behavior Uncovers Topological Close-Packing and Epitaxial Quasicrystal Growth'. Together they form a unique fingerprint.

Cite this