Issue 32, 2017

Heating-induced negative temperature coefficient effect in conductive graphene/polymer ternary nanocomposites with a segregated and double-percolated structure

Abstract

Electrically conductive polymer composites (CPCs) show considerable promise in thermistors owing to their characteristics of positive temperature coefficient (PTC) effect and negative temperature coefficient (NTC) effect of resistance. In contrast to traditional rigid ceramic thermistors, CPCs are lightweight with good processibility, flexibility and variety. However, the development of polymer-based NTC thermistors has been impeded by the polymer volume expansion effect, which usually leads to a PTC effect. Here, we employed a segregated and double-percolated composite microstructure to inhibit the polymer volume expansion effect and flake-like graphene as conductive filler to construct a resistant conductive network by its overlapping contact mode, targeted at developing a favorable NTC material. This strategy was carried out by selectively distributing graphene in a polyamide 6 (PA6) phase between isolated ultrahigh molecular weight polyethylene (UHMWPE) particles. As a result, the graphene/PA6/UHMWPE composites exhibited a relatively linear NTC effect through the whole heating process, a high NTC intensity of 5.1, a wide temperature range of 30–260 °C, good reproducibility as well as high mechanical properties. The underlying mechanism of the NTC effect originates from the morphology evolution from crumpled to stretched morphology, enhanced electron mobility in the crumpled morphology, and the improved conductivity of graphene triggered by increasing the temperature.

Graphical abstract: Heating-induced negative temperature coefficient effect in conductive graphene/polymer ternary nanocomposites with a segregated and double-percolated structure

Supplementary files

Article information

Article type
Paper
Submitted
05 jún 2017
Accepted
18 júl 2017
First published
18 júl 2017

J. Mater. Chem. C, 2017,5, 8233-8242

Heating-induced negative temperature coefficient effect in conductive graphene/polymer ternary nanocomposites with a segregated and double-percolated structure

S. Zhao, D. Lou, P. Zhan, G. Li, K. Dai, J. Guo, G. Zheng, C. Liu, C. Shen and Z. Guo, J. Mater. Chem. C, 2017, 5, 8233 DOI: 10.1039/C7TC02472J

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements