Electrostatic induced self-assembled MXene/EPOSS for high-performance electromagnetic interference shielding materials

It is still a challenge to prepare flexible electromagnetic interference (EMI) shielding materials based on Ti3C2Tx MXene through a facial and scalable method. In this study, epoxied octamethyl-cyclotetrasiloxane (EPOSS) was self-assembled with Ti3C2Tx to construct EMI shielding composites via facial spraying coating. Because the EPOSS decreased the surface free energy of Ti3C2Tx in the acid-base component, the Ti3C2Tx/EPOSS suspension was able to be sprayed on carboxylated polybutadiene (CPB) uniformly. Molecular dynamics (MD) simulations were explored to demonstrate the interaction energy between EPOSS and CPB with different –COOH contents. The prepared EMI shielding composite has high abrasion resistance and good bending durability because EPOSS reinforced the interface interaction between Ti3C2Tx and CPB through covalent bonds. Based on a pre-stretching spray method, the prepared composite has high surface roughness, leading to a high specific EMI shielding effectiveness of 1800 dB cm2 g−1 at a low Ti3C2Tx loading of 8.5 wt%. Additionally, the physically protective effect of Si–O–Si cages in EPOSS provided good flame retardancy. Therefore, the proposed EPOSS-assisted Ti3C2Tx spraying strategy could prepare EMI shielding materials with high effectiveness, excellent abrasion resistance, and good flame retardancy, which has a broad prospect for the application of high-power, portable, and wearable flexible electronic devices.