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Nanocomposites of Au/Disentangled UHMWPE: A combined optical and structural study

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journal contribution
posted on 06.08.2020, 13:39 authored by Stavros Drakopoulos, Oreste Tarallo, Lin GuanLin Guan, Nacho Martin-Fabiani-CarratoNacho Martin-Fabiani-Carrato, Sara Ronca
The term disentangled refers to polymers with fewer entanglements in the amorphous regions, a metastable condition that can significantly affect the material's properties and processing behavior. The lower entanglement density in ultra-high molecular weight polyethylene (dis-UHMWPE) facilitates the solid-state processability into uniaxially-oriented specimens reaching very high draw ratios and crystallinities. In this study, Au/dis-UHMWPE nanocomposites were formulated and processed at variable draw ratios. Polarized light microscopy suggests gold nanoparticles are oriented in arrays following the drawing of polymer chains. The structural features, upon orientation, are studied by means of Raman spectroscopy, wide- and small-angle X-ray scattering, and near-infrared spectrophotometry. Crystallinity is found to increase by 15%, as calculated by wide-angle X-ray scattering. The change in optical absorbance in the visible spectrum indicates that, with orientation, the average size of gold aggregates increases, supported quantitatively by small-angle X-ray scattering. Since the gold nanoparticles are expected to be found within amorphous chain segments, the aforementioned findings are attributed to the increase of crystallinity and thus the decrease of available (amorphous) space.

History

School

  • Aeronautical, Automotive, Chemical and Materials Engineering

Department

  • Materials

Published in

Molecules

Volume

25

Issue

14

Pages

3225

Publisher

MDPI

Version

VoR (Version of Record)

Rights holder

© The authors

Publisher statement

This is an Open Access Article. It is published by MDPI under the Creative Commons Attribution 4.0 Unported Licence (CC BY). Full details of this licence are available at: http://creativecommons.org/licenses/by/4.0/

Acceptance date

13/07/2020

Publication date

2020-07-15

Copyright date

2020

eISSN

1420-3049

Language

en

Depositor

Dr Nacho Martin-Fabiani Carrato. Deposit date: 4 August 2020

Article number

3225