Multifunctional-structural integrated wood cellulose‑based composite with Magpie’s Nest-shaped enhance flame retardancy and electromagnetic interference shielding

The construction of multifunctional hydrophobic wood with electromagnetic interference shielding effectiveness had attracted great interest, at the same time, the problem of wood flammability must also be solved. In this study, the effectiveness of DOPO-based P and Zn complexes in improving wood flame retardancy and electromagnetic interference shielding effectiveness, and the outstanding contribution of lignocellulose skeleton and multi-interface to shielding effectiveness was demonstrated. DOPO-based P and Zn complexes with “Needle-punched” structure and much functional groups were loaded on the wood surface, and then micro-nano metal Ni particles were deposited. Through the optimization of the wood surface and itself structure, and the construction of a complete conductive network. Wood/ZnP/Ni composites electromagnetic interference shielding effectiveness couold reach 65.04 dB in the X-band. It was worth noting that the lignocellulose skeleton prepared by the top-down method and multi-interface structure increase electromagnetic interference shielding effectiveness by 10.71 % and 33.89 %, respectively. In addition, the synergistic effect of DOPO-based P and Zn complexes and the introduction of PDMS layer improved the flame retardancy (limiting oxygen index was 35.3 %) and hydrophobicity (contact angle was 133.07°), which avoided the wood poor durability problem in use. There was no doubt that it provided a new strategy for the preparation of novel materials with low-cost and extremely excellent electromagnetic interference shielding properties.