Constructing PAM/PEG electromagnetic shielding hydrogels based on MWCNTs@TiO2

Abstract

With the widespread popularity of digital technology, electromagnetic interference(EMI) has become a new type of pollution that endangers electronic equipment and biological systems. In this paper, MWCNTs@TiO₂ composite materials were prepared by the hydrothermal synthesis method and then added into the three dimensional framework constructed by PAM (polyacrylamide) and PEG (polyethylene glycol) to obtain hydrogels with EMI functionality. It was found that in the M@T/PAM-4 (MWCNTs@TiO₂/PAM-4) hydrogel, due to the fact that TiO₂ particles were loaded on the surface of MWCNTs, its cross section presented a granular shape. As the content of MWCNTs increased, the EMI SE_T of the hydrogel increased, with the M@T/PAM-4 hydrogel reaching 29 dB. The electrical conductivity and mechanical properties also increased accordingly. Compared with the pure PAM hydrogel, they were respectively improved by 626 % and 24.5 %, which was attributed to the formation of a conductive network by MWCNTs and the enhancement of interfacial polarization, etc. Meanwhile, the water retention rate of the M@T/PAM-4 hydrogel could still reach 34.1 % after 8 h. Moreover, it also had a relatively high water content of 69.08 %. Therefore, This improves the application value and development prospects of the hydrogel in fields such as Electromagnetic (EM) shielding.