Recyclable cellulose-based paper from bleached eucalyptus pulp with high electromagnetic shielding and excellent...

Practical electromagnetic interference (EMI) shielding materials are hard to combine light weight, flexibility, processability and high effectiveness. Conductive PEDOT@EPF fibers were prepared by in situ oxidative polymerization poly(3,4-ethylenedioxythiophene) (PEDOT) on bleached eucalyptus pulp fibers. Carbon fibers were chemically modified (MCF) to introduce surface groups, improving dispersion and interfacial adhesion with PEDOT@EPF. These two conductive fibers were blended and formed into cellulose composite paper via wet-laid papermaking. The optimized composite shows 787 S m^-1 in conductivity. With a surface density of 240 g m^-2, its total EMI SE_T reaches 62 dB across X-band (8.2-12.4 GHz), blocking >99.99% of radiation. After 5 repulping and reforming cycles, 95% of initial SE_T is retained. The material exhibits a tensile strength of 18.2 MPa, with only a 28% reduction after five cycles, maintaining excellent mechanical properties. It exhibits a relatively low bulk density (0.30-0.45 g cm^-3), combining lightweight properties with excellent mechanical performance. Large-area sheets (1.8 m × 1.2 m) are produced via wet-laid technique, and the composite retains cutting, bending and folding ability like paper. This work offers a practical route to recyclable cellulose-based EMI shielding materials for wearables, electronics and industrial protection.