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Title: Dual Ionic Liquid-Functionalized Cellulosic Materials: Thermal, Conductive, and Morphological Properties
Dual ionic liquid-substituted cellulosic materials were prepared by coupling a series of alkyne-terminated imidazoles with variable carbon spacer with azide-functionalized cellulose, followed by quaternization and anion exchange. All three of the [NTf2]-bearing cellulosic materials exhibited Tg values below zero and could be cast as flexible films, which exhibited stress at break values exceeding 2.3 MPa with strain at break values up to 252%. X-ray scattering analyses indicated the amorphous nature of the cellulosic materials with three scattering peaks observed, from high-to-low q, corresponding to the amorphous halo, anion-to-anion distance, and the distance between ion aggregates, respectively. The highest degree of ionic aggregation was found to exist in the CELL-C12-NTf2 material, presumably due to the longer alkyl tethers causing more uniformity in the interaggregate spacing. The conductivity of the films was found to be on the order of 10−5−10−6 S/cm at 30 °C. A slower increase in conductivity with temperature was observed for systems where ionic aggregation was the strongest.  more » « less
Award ID(s):
2104375
PAR ID:
10494277
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
American Chemical Society
Date Published:
Journal Name:
ACS Applied Polymer Materials
ISSN:
2637-6105
Subject(s) / Keyword(s):
cellulose click chemistry poly(ionic liquid) morphology ionic conductivity
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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