Literature by the same author
plus at Google Scholar

Bibliografische Daten exportieren
 

Reversible transition between isotropic and anisotropic thermal transport in elastic polyurethane foams

Title data

Chau, Mokit ; Kopera, Bernd A. F. ; Machado, Vanessa R. ; Tehrani, Sepehr Mastour ; Winnik, Mitchell A. ; Kumacheva, Eugenia ; Retsch, Markus:
Reversible transition between isotropic and anisotropic thermal transport in elastic polyurethane foams.
In: Materials Horizons. Vol. 4 (2017) Issue 2 . - pp. 236-241.
ISSN 2051-6355
DOI: https://doi.org/10.1039/C6MH00495D

Project information

Project financing: VolkswagenStiftung

Abstract in another language

The dynamic and orientational control over the flow of heat is becoming increasingly important in current insulation applications. In this contribution we introduce an elegant way to fabricate highly anisotropic polyurethane foams via freeze casting from an aqueous dispersion. Such elastic foams demonstrate not only orientation dependent Young’s moduli, but also a good recoverability after compression. Most importantly, they are distinctly more insulating across their perpendicular than their parallel orientation. This anisotropy, however, can be turned on and off by appropriate choice of the gas phase. The thermal anisotropy is lost and an isotropic thermal transport is observed, when using Helium as gas phase. The degree of anisotropy can be adjusted via the gas pressure or the gas composition. We demonstrate that one can dynamically and reproducibly transition between such modes of isotropic and anisotropic thermal transport.

Further data

Item Type: Article in a journal
Refereed: Yes
Institutions of the University: Faculties > Faculty of Biology, Chemistry and Earth Sciences > Department of Chemistry
Faculties > Faculty of Biology, Chemistry and Earth Sciences > Department of Chemistry > Chair Physical Chemistry I
Faculties > Faculty of Biology, Chemistry and Earth Sciences > Department of Chemistry > Former Professors > Chair Physical Chemistry I - Univ.-Prof. Dr. Stephan Förster
Profile Fields > Advanced Fields > Polymer and Colloid Science
Faculties
Faculties > Faculty of Biology, Chemistry and Earth Sciences
Profile Fields
Profile Fields > Advanced Fields
Faculties > Faculty of Biology, Chemistry and Earth Sciences > Department of Chemistry > Former Professors
Result of work at the UBT: Yes
DDC Subjects: 500 Science > 540 Chemistry
Date Deposited: 03 Jan 2017 07:49
Last Modified: 08 Feb 2022 14:48
URI: https://eref.uni-bayreuth.de/id/eprint/35610