Thermally Conductive Polyethylene/Expanded Graphite Composites as Heat Transfer Surface: Mechanical, Thermo-Physical and Surface Behavior

<p dir="ltr">Composites of high-density polyethylene (HDPE) and expanded graphite (EG) are prepared for heat exchangers in multi-effect distillation (MED) desalination. At 50 wt.% EG loading, the thermal conductivity of HDPE was increased by 372%. Moreover, the surface wettability of...

Full description

Saved in:
Bibliographic Details
Main Author: Patrik Sobolčiak (4401364) (author)
Other Authors: Asma Abdulgader (18561187) (author), Miroslav Mrlik (5477618) (author), Anton Popelka (2804842) (author), Ahmed A. Abdala (18561190) (author), Abdelnasser A. Aboukhlewa (18561193) (author), Mustapha Karkri (18561196) (author), Hendrik Kiepfer (18561199) (author), Hans-Jörg Bart (2649340) (author), Igor Krupa (1389267) (author)
Published: 2020
Subjects:
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:<p dir="ltr">Composites of high-density polyethylene (HDPE) and expanded graphite (EG) are prepared for heat exchangers in multi-effect distillation (MED) desalination. At 50 wt.% EG loading, the thermal conductivity of HDPE was increased by 372%. Moreover, the surface wettability of the HDPE/EG composite was enhanced by corona and RF plasma treatment as demonstrated by the increase in surface free energy from 28.5 mJ/m2 for untreated HDPE/EG to 55.5 and 54.5 mJ/m2 for HDPE/EG treated by corona and RF plasma, respectively. This enhanced surface wettability was retained over a long time with only a 9% and 18% decrease in RF and corona plasma-treated samples’ surface energy after two months. The viscoelastic moduli and the complex viscosity profiles indicated that EG content dictates the optimum processing technique. At loading below 30 wt.%, the extrusion process is preferred, while above 30 wt.% loading, injection molding is preferred. The plasma treatment also improved the HDPE/EG composite overall heat transfer coefficient with an overall heat transfer coefficient of the composite reaching about 98% that of stainless steel. Moreover, the plasma-treated composite exhibited superior resistance to crystallization fouling in both CaSO4 solution and artificial seawater compared to untreated composites and stainless-steel surfaces.</p><h2>Other Information</h2><p dir="ltr">Published in: Polymers<br>License: <a href="https://creativecommons.org/licenses/by/4.0/" target="_blank">https://creativecommons.org/licenses/by/4.0/</a><br>See article on publisher's website: <a href="https://dx.doi.org/10.3390/polym12122863" target="_blank">https://dx.doi.org/10.3390/polym12122863</a></p>