Reversibly cross-linked SEBS/carbon hybrid composite with excellent solvent-proof and electromagnetic shielding properties

Publication date: 15 May 2018
Source:Materials & Design, Volume 146
Author(s): Yu Xu, Shumei Tang, Jingkai Pan, Jianjun Bao, Aimin Zhang
Herein, a novel design of reversibly cross-linked, solvent-proof and electromagnetic (EMI) shielding SEBS/carbon hybrid composites with remoldability was proposed based on the thermally dragged Diels-Alder (D-A) reaction. New furan grafted SEBS (Fur-SEBS) precursors differing in furan grafting ratios were successfully synthesized by successive modifications, including chloromethylation, esterification, hydroxylation and furan grafting reaction. 2-Furfurylamine modified reduced graphene oxide (FG) nanoplatelets were also designed as reactive fillers to participate in the D-A reaction. Both of them could be reversibly crosslinked by bismaleimide, which resulted in good solvent-proof, mechanical and microwave absorption properties of target composites without sacrifice of remoldability. The composite with chloromethylation time of 9h and 2wt% FG achieved a swelling degree of 4%, a gel content of 90% and a tensile strength of 10.5MPa, which showed the best comprehensive performance. Moreover, the FG was also confirmed to decrease the electrical conductivity but significantly enhance the electromagnetic wave absorbing ability of SEBS/carbon nanotube (CNTs) hybrid composite, due to the improved filler dispersion, impedance match at air-sample interface and multi-scale synergy effects with CNTs. The reversibly cross-linked composites were promising candidates for a range of applications, more specifically, signal cable, EMI shielding seal washer and melt adhesive.

Graphical abstract

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