Hierarchically Structured Cellulose Acetate@Silk Protein Membrane with Enhanced Mechanical and Electromagnetic...

Area of Science:

• Materials Science
• Nanotechnology
• Composite Materials

Background:

• Hierarchical porous nanofibers offer increased active sites and internal spaces, boosting functional material performance.
• Conventional fibers lack the structural complexity for advanced applications.

Purpose of the Study:

• To construct coaxial composite cellulose acetate@silk fibroin (CA@SF) fibrous membranes with hierarchical structures.
• To evaluate the electromagnetic shielding and mechanical properties of these novel membranes.

Main Methods:

• Electrostatic spinning combined with solvent-induced phase separation to create hierarchical core-shell structures.
• Electroless deposition of silver (Ag) nanoparticles onto the fibrous membranes.
• Post-treatment with ethanol to enhance mechanical properties.

Main Results:

• Hierarchical CA@SF fibers exhibit increased surface area, improved mechanical properties, and enhanced flux.
• The CA@SF@Ag composite membrane achieved a total electromagnetic shielding efficiency of 100 dB at 100 μm thickness.
• Ethanol post-treatment improved tensile strength to 10 MPa for a 50 μm thick membrane.

Conclusions:

• The developed hierarchical CA@SF@Ag membranes show superior electromagnetic shielding capabilities compared to nonhierarchical structures.
• These findings demonstrate the potential of electrospun hierarchical fiber membranes for ultrathin electromagnetic shielding applications.