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  • In situ investigation of the rheological and dielectric properties of a cross-linking carbon nanotube-thermosetting epoxy
Title: In situ investigation of the rheological and dielectric properties of a cross-linking carbon nanotube-thermosetting epoxy
Radio-frequency (RF) heating of thermosetting epoxies is an agile method to decouple the extrudability of epoxy resins from their buildability for additive manufacturing. Through this method, the resin is extruded in the liquid state at the early stages of curing. Then, an RF applicator induces a rapid and uniform increase in temperature of the resin, accelerating the solidification of the printed feature. Understanding the evolution of the resin's RF heating response as it cures is therefore critical in meeting the demands of additive manufacturing. In this work, we show that the high-frequency dielectric loss, determined using in situ rheo-dielectric measurements, of both neat and carbon nanotube (CNT) filled resins is correlated to the heating response at different temperatures throughout curing. Furthermore, we show that the presence of CNTs within the resin augments the heating response and that their dispersion quality is critical to achieving rapid heating rates during the cure.  more » « less
Award ID(s):
2047365
PAR ID:
10609718
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
Royal Society of Chemistry
Date Published:
Journal Name:
Soft Matter
Volume:
19
Issue:
32
ISSN:
1744-683X
Page Range / eLocation ID:
6168 to 6175
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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