Study on structural and functional properties of porous SiO2 core‐shell construction/polyethylene nanocomposites with enhanced interfacial interaction

The addition of inorganic particles can endow polymer matrices with different new features, thereby realizing an optimization to the structural and functional properties of composite. The overall properties of composites are greatly influenced by both fillers dispersion and fillers‐polymer interfacial interaction. However, to simultaneously improve these mentioned two issues is still a critical challenge in the field of polymer‐based nanocomposite. Herein, a typical core‐shell structured mesoporous silica‐coated silica (SiO2@mSiO2) construction was successfully synthesized by using a bi‐phase method. The SiO2@mSiO2 filled polyethylene (PE) nanocomposite was fabricated through a precisely controlled melt‐mixing approach. Benefiting from the additional mesoporous SiO2 shell, both the dispersion of SiO2@mSiO2 and the SiO2@mSiO2‐PE matrix interfacial interaction are improved. Moreover, the stress–strain behavior, temperature‐dependent mechanical property, thermal stability, and electrical insulating property of SiO2@mSiO2/PE composite were studied in detail. It is found that SiO2@mSiO2 core‐shell nanoparticles are capable of not only making a balance between the strength and toughness of the PE‐based composite, but also improving the thermal stability of the composite. In addition, the SiO2@mSiO2/PE composite exhibited an enhanced breakdown strength (256.4 MV·m−1) when filled with as small as 1 wt% SiO2@mSiO2, which is 108% higher than neat PE. All these optimized features are attributed to the well‐designed core‐shell structure. These experimental results provide a promising way to design and fabricate future advanced composite with excellent structural and functional properties in the future.