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Metallic-like thermal conductivity in a lightweight insulator: solid-state processed Ultra High Molecular Weight Polyethylene tapes and films
journal contribution
posted on 2017-07-26, 10:34 authored by Sara Ronca, Tamito Igarashi, Giuseppe Forte, Sanjay RastogiUltra High Molecular Weight Polyethylene with a reduced number of entanglements can be stretched in the solid state both uni- or biaxially to produce highly oriented tapes and films. The chain orientation, in combination with the reduced number of chain ends, is responsible for the high tensile modulus and tensile strength of the drawn materials, and, as we report here, also for the high thermal conductivity achieved through lattice movements. A property such as thermal conductivity in an electrical insulator makes UHMWPE tapes and films of great applicative interest. In-plane laser-flash thermal analysis has been applied to measure the thermal diffusivity of samples of different molecular weights stretched both uni- and biaxially, and a strong correlation has been found between the drawing ratio and the resulting in-plane thermal conductivity. Values of at least 40 W/m K have been achieved for UHMWPE having Mw comprised between 2 and 10 million, while higher values of 65 W/m K are observed for the higher Mw samples having relatively lesser number of chain ends. Surprisingly the biaxially stretched samples also show in-plane conductivity, with the highest value reaching 18 W/m K, comparable to stainless steel.
Funding
This project has been funded by the Engineering and Physical Science Research Council (EPSRC), grant EP/K034405/1.
History
School
- Aeronautical, Automotive, Chemical and Materials Engineering
Department
- Materials
Published in
PolymerCitation
RONCA, S. ... et al., 2017. Metallic-like thermal conductivity in a lightweight insulator: solid-state processed Ultra High Molecular Weight Polyethylene tapes and films. Polymer, 123 (August), pp. 203–210.Publisher
© The Authors. Published by Elsevier Ltd.Version
- VoR (Version of Record)
Publisher statement
This work is made available according to the conditions of the Creative Commons Attribution 4.0 International (CC BY 4.0) licence. Full details of this licence are available at: http://creativecommons.org/licenses/ by/4.0/Acceptance date
2017-07-09Publication date
2017Notes
This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).ISSN
0032-3861Publisher version
Language
- en