Yao, X., Cseh, L., Zeng, X. et al. (3 more authors) (2017) Body-centred cubic packing of spheres-the ultimate thermotropic assembly mode for highly divergent dendrons. Nanoscale Horizons, 2 (1). pp. 43-49. ISSN 2055-6756
Abstract
We have synthesized sodium tris(alkoxy)benzoates in which one of the three alkyl chains branches further into three C 18 H 37 chains. These AB5 hyperbranched minidendrons melt directly into a body-centred cubic (BCC) mesophase formed by spherical "micelles". In contrast, their non-branched counterparts display various mesophases before they turn into BCC upon heating. This agrees with the predictions from a numerical geometric model that relates the shape of the molecular wedge to the type of mesophase they adopt. The spheres were found to shrink in volume upon heating and expand upon cooling, as molecules, in some cases nearly half of them, are ejected and reintegrated in the spheres. The ejection of dendrons is caused by their lateral thermal expansion. The BCC appears to be the ultimate mesophase for the extremely divergent wedges such as the hyperbranched minidendrons. In dendrons with chains of unequal length, the sphere size is fixed by the shorter chains, the longer ones back-folding or interdigitating to effectively widen the wedge. This new understanding of their assembly will help in designing new dendrons, e.g. for better encapsulation of guest molecules.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | © Royal Society of Chemistry 2017. This is an author-produced version of a paper accepted for publication in Nanoscale Horizons. Uploaded in accordance with the publisher's self-archiving policy. |
Dates: |
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Institution: | The University of Sheffield |
Academic Units: | The University of Sheffield > Faculty of Engineering (Sheffield) > Department of Materials Science and Engineering (Sheffield) |
Funding Information: | Funder Grant number LEVERHULME TRUST (THE) RPG-2012-804 ENGINEERING AND PHYSICAL SCIENCE RESEARCH COUNCIL (EPSRC) EP/K034308/1 |
Depositing User: | Symplectic Sheffield |
Date Deposited: | 20 Feb 2018 13:11 |
Last Modified: | 20 Feb 2018 13:16 |
Published Version: | https://doi.org/10.1039/c6nh00155f |
Status: | Published |
Publisher: | Royal Society of Chemistry |
Refereed: | Yes |
Identification Number: | 10.1039/c6nh00155f |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:127689 |