Phase Behavior of Linear-Bottlebrush Block Polymers

Lucy Liberman Solomon, Tim Lodge, McKenzie L Coughlin, Steven Weigand, Frank S Bates

Research output: Contribution to journalArticlepeer-review

Abstract

Block copolymers (BCPs) self-assembled into 3D network phases are promising for designing useful materials with multiple properties that rely on domain continuity. However, access to potential applications has been limited because network formation with linear BCPs tends to occur only over narrow compositional windows. Another constraint is slow self-assembly kinetics at higher molecular weights, which limits the network unit cell dimensions and the resulting material properties. Architecturally asymmetric, linear-bottlebrush BCPs have previously been demonstrated to promote self-assembly into complex micellar phases. The architectural asymmetry has been demonstrated to induce favorable curvature toward the linear block. However, linear-bottlebrush copolymer phase behavior and self-assembly into network phases have not been systematically studied. Here, we map the phase behavior of eight sets of diblock polymers with a linear-bottlebrush architecture in the expected vicinity of the double-gyroid phase. We demonstrate the effects of architectural asymmetry and the linear block cohesive energy density on self-assembly into double-gyroid, lamellar, and hexagonal phases. Through a combination of molecular and structural characterization techniques, we demonstrate that the shape of the polymer and the identity of the linear block provide significant control over the molecular factors that dictate network formation.

Original languageEnglish (US)
Pages (from-to)2821-2831
Number of pages11
JournalMacromolecules
Volume55
Issue number7
DOIs
StatePublished - Apr 12 2022

Bibliographical note

Funding Information:
This work was supported by the National Science Foundation through the University of Minnesota MRSEC under award number DMR-2011401. Synchrotron SAXS experiments were performed at the 12-ID-B and 5-ID-D beamlines of the Advanced Photon Source (APS). This research used resources of the Advanced Photon Source, a U.S. Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Argonne National Laboratory under contract no. DE-AC02-06CH11357. We thank Dr. Aaron Lindsay for his help with the collection of rheology and DSC data, Dr. David Giles for discussion and help with rheology and DSC measurements, and Prof. Mahesh Mahanthappa for fruitful discussions.

Publisher Copyright:
© 2022 The Authors. Published by American Chemical Society and Division of Chemical Education, Inc.

How much support was provided by MRSEC?

  • Primary

Fingerprint

Dive into the research topics of 'Phase Behavior of Linear-Bottlebrush Block Polymers'. Together they form a unique fingerprint.

Cite this