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Title: Thermal Conduction and Phonon Transport in Folded Polyethylene Chains
Using theory and simulations, we have investigated the phonons and their role in thermal energy transport in semicrystalline polyethylenes. Considering alternating stacks of lamellae and amorphous regions, and labeling one polyethylene chain interwoven among two amorphous regions and one lamella, we have explored the underlying mechanism of thermal conductivity of polyethylene in its semicrystalline state. We report that hairpin-like folds at the crystalline–amorphous interface significantly scatter phonons, allowing only less than half of the phonons to transmit through polyethylene backbone. Monitoring the phonon propagation and scattering at the interfaces, we have computed thermal conductivity of semicrystalline polyethylene. We have derived a design principle to control thermal conductivity of semicrystalline polyethylene in terms of lamellar thickness and the number of folds per chain at the crystalline–amorphous interface.  more » « less
Award ID(s):
2015935
PAR ID:
10498939
Author(s) / Creator(s):
;
Publisher / Repository:
American Chemical Society
Date Published:
Journal Name:
Macromolecules
Volume:
56
Issue:
2
ISSN:
0024-9297
Page Range / eLocation ID:
393 to 403
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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