Flexible and hydrophobic polyimide/MXene-POSS nanocomposite films for electromagnetic interference shielding

A strategy for fabricating polyimide(PI)/MXene-POSS nanocomposite films with excellent electromagnetic interference (EMI) shielding, water resistance, and flame retardance was developed. Herein, the hydrophobic MXene-POSS hybrid was successfully prepared by modifying MXene with polyhedral oligomeric silsesquioxane (POSS). On the one hand, MXene-POSS has good compatibility with PI, so that uniform films can be prepared; on the other hand, the prepared composite films have hydrophobic properties, improving their application in extreme environments. The nanocomposite film with 20 wt% MXene-POSS content achieved a desirable EMI shielding performance of 12.7 dB. In addition, the PI/MXene-POSS nanocomposite also exhibited excellent fire resistance. Moreover, due to the hydrophobic properties of the PI/MXene-POSS-20 % nanocomposite, the water uptake of the PI/MXene-POSS-20 % nanocomposite film was approximately 1.4 % under 70 % relative humidity. The PI/MXene-POSS nanocomposite film demonstrates reasonable EMI shielding performance with high stability and durability, which has the potential for broad applications in electronic devices designed for use in extreme outdoor environments.