Highly stretchable and self-foaming polyurethane composite skeleton with thermally tunable microwave absorption properties

Fengchao Ye; Xinsheng He; Jiajia Zheng; Yancheng Li; Mengjia Li; Zhonglue Hu; Sisi Wang; Guoxiu Tong; Xiping Li

doi:10.1088/1361-6528/abe9e7

Highly stretchable and self-foaming polyurethane composite skeleton with thermally tunable microwave absorption properties

Nanotechnology. 2021 Mar 12;32(22). doi: 10.1088/1361-6528/abe9e7.

Authors

Fengchao Ye¹, Xinsheng He¹, Jiajia Zheng¹, Yancheng Li², Mengjia Li¹, Zhonglue Hu¹, Sisi Wang¹, Guoxiu Tong³, Xiping Li¹

Affiliations

¹ Key Laboratory of Urban Rail Transit Intelligent Operation and Maintenance Technology & Equipment of Zhejiang Province, College of Engineering, Zhejiang Normal University, Jinhua, 321004, People's Republic of China.
² School of Civil and Environmental Engineering, University of Technology Sydney, Sydney 2007, New South Wales, Australia.
³ College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua 321004, People's Republic of China.

PMID: 33631730
DOI: 10.1088/1361-6528/abe9e7

Abstract

Stretchable and lightweight polymer composite material possessing tunable microwave absorption (MA) properties under thermal radiations remain a significant challenge. Here, we proposed a facile strategy to fabricate stretchable, magnetic composite skeletons by incorporating the tadpole-like CNTs@Fe₃O₄nanoparticles into self-foaming polyurethane (PU) matrix and the electromagnetic responsive of CNTs@Fe₃O₄/PU composite foams with different CNTs contents under heating-cooling cycle in a temperature range of 253 -333 K were carefully investigated. Enhanced complex permittivity and shifting peak frequency were observed at elevated temperatures. For instance, the 70-CNTs@Fe₃O₄/PU sample with 15 wt% loading content at 333 K exhibits excellent MA properties including a minimum reflection loss (RL_m) of -66.9 dB and ultrabroad effective frequency bandwidth (RL ≤ -20 dB) of 9.98 GHz at the thickness of 1.58-3.37 mm. Meanwhile, great recoverability in terms of RL-fprofile was achieved in the process of thermal cooling back to 253 K. Such adjustable MA property was attributed to the well-matched impedance and dramatic attenuation ability, benefiting from the temperature-dependant electrical conductivity, abundant interfacial polarization and interior microcellular structures. Besides, the rising temperature increased the sample elongation and electrical conductivity with a slight sacrifice of maximum tensile strength. This stretchable PU skeleton with a unique assembly of CNTs and Fe₃O₄nanoparticles are expected to be promising candidates as smart absorbers for application in the harsh environments.

Keywords: CNTs@Fe3O4 nanoparticles; microwave absorption; polyurethane skeleton; self-foaming; thermally tunable.