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Excellent stability of a catalytic center would facilitate the prolongation of the cycle of a chemical plating bath and the reduction of environmental pollution. In this study, silane (3-aminopropyltriethoxysilane (KH550) and γ-(2,3-epoxypropoxy)­propytrimethoxysilane (KH560)) was incorporated in AgNO3 solution to rationally prepare a Ag nanoparticle/polymer brush (Ag/PB) catalytic solution. The effects of the KH560 relative content on the Ag/PB structure and stability were studied. The epoxy group in the KH560 could react with an amino group in the KH550 through direct ring-opening reaction to form a secondary amino group and hydroxyl, which could coadsorb Ag nanoparticles by means of a chelating structure; hence, Ag/PB with superior Ag-adsorbed intensity was established on a polyethylene terephthalate (PET) surface. Ag particles on PB with 75% KH560 revealed the best stability of those measured, and the relative Ag surplus was 56.7% after stability testing. The generated Ag/PB that served as catalytic centers to catalyze the electroless copper plating resulted in a facile technology for preparing Cu/PET composite material. This means that the technology has potential application in a green process for preparing metal/polymer composite materials.

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The exploration of flexible and lightweight electromagnetic interference (EMI) shielding materials with excellent shielding effectiveness, as a means to effectively alleviate electromagnetic pollution, is still a tremendous challenge. This paper proposes a conducting material named the textured Ni-encapsulated carbon tube, which can be applied in EMI shielding material by being inserted in the center of a poly(dimethysiloxane) (PDMS) polymer. We demonstrated that Pd 2+ could be absorbed by the active groups on the plant fiber surface to catalyze the reduction of Ni 2+ as a catalytic center by means of a textured Ni-encapsulated plant fiber. Owing to the outstanding heat-conducting capability of the Ni coating, the inner plant fiber was carbonized and attached to the Ni-tube inside the surface during annealing. To be precise, the textured Ni-encapsulated C tube was fabricated successfully after annealing at 300 °C. On further increasing the annealing temperature, the C tube disappeared gradually with the Ni coating being oxidized to NiO. Of note, the C tube acted as a support layer for the external Ni coating, providing sufficient mechanical strength. When combined with the coating PDMS layer, a flexible and lightweight EMI shielding material is fabricated successfully. It displays an outstanding EMI shielding effectiveness of 31.34 dB and a higher specific shielding efficiency of 27.5 dB•cm 3 /g, especially showing excellent mechanical property and flexibility with only 2 mm thickness. This study provides a new method to fabricate outstanding EMI shielding materials.

Multi-ion fabrics (especially silver ion fabrics) have special advantages as electromagnetic radiation, but the use of noble metals enhances its cost. Electroless nickel plating (EP-Ni) has great potential application in fabricating low-cost metallized material. Here, EP-Ni on pure cotton surface to fabricate radiation protection suits for pregnant woman was established to replace traditional protection suits with silver film. The active groups on the cotton/polyester blend fiber surface could absorb tin and palladium ions, acting as catalytic centers, which can catalyze the reduction of Ni2+ in the plating solution. Ni particle with (111) crystal plane preferential oriented crystal structure deposited on cotton surface with a coarse microstructure. The Ni deposited amount is about 19%. The fabricated material exhibited a shielding effectiveness of 29.5 dB. Studies also shown that bending has no negative effect on crystallinity and electrical property. But more bending times could lead to crack, which would decline electromagnetic shielding performance by 24%.