Robust integration of p-MXene ink with bacterial cellulose-reinforced polymer enables dynamic interaction of superior electromagnetic shielding and sensing

The rapid development of intelligent wearable devices and health monitoring equipment demands bio-based materials that integrate multiple functions with enhanced durability. Herein, this work is an first attempt to develop flexible electromagnetic shielding and stress-strain sensing based on a composite of polydopamine (PDA) modified-MXene (p-MXene) film with waterborne polyurethane (WPU)/bacterial cellulose (BC) film. The durable p-MXene@WPU/BC composite films are found to demonstrate excellent mechanical properties (370 MPa) and stable interfacial adhesion, attributing to the interlocking network structure between WPU and WBC and the strong hydrogen bonding between p-MXene layer and WPU/BC layer. The resultant composite film displays remarkable mechanosensing performance, facilitating the accurate and reliable detection of human physiological signals. Importantly, the prepared composite film could effectively reflect and absorb electromagnetic waves through the high conductivity of p-MXene layer and the staggered nanonetwork structure of WPU/BC layer, thus achieving a shielding effect of up to 72 dB. As proof-of-concept illustrations, it is noteworthy that the electromagnetic shielding efficacy displays a dynamic interaction with the strain sensing performance during the stretching process, which is primarily attributed to the moderating effect of the efficient attachment and parallel-aligned structure of p-MXene nanosheets. The research herein can offer new perspectives on the development of advanced bio-based multiple functions materials and dynamic perceptual interaction and smart wearables.