New promising hybrid materials for electromagnetic interference shielding with improved stability and mechanical properties.

A novel transparent Co0.2Fe2.8O4@SiO2-polyetheretherketone hybrid material is prepared for electromagnetic interference shielding via in situ sol-gel process. 20% amino-functionalized polyetheretherketone (AFPEEK), containing trifluoromethyl units with excellent solubility is designed and synthesized to improve the stability and mechanical properties of Co0.2Fe2.8O4@SiO2 nanoparticles. The hydrophilic nanoparticles and hydrophobic polymer matrix are covalently connected after the effective interface modification with 3-isocyanatopropyltriethoxysilane. SEM and TEM images demonstrate that the strong interaction between inorganic-organic phases results in great improvement of dispersion and compatibility at even 40 wt% nanoparticles contents. The functional integration of organic polymer and inorganic nanoparticles leads to excellent comprehensive performances such as high transparency, thermal stability and mechanical properties of the hybrid material, as well as the high adhesion with substrate, which benefits its application as coating materials. This high performance material exhibits good superparamagnetic behaviour and microwave electromagnetic properties (RLmax ∼ -13 dB), which can be utilized as a promising electromagnetic interference shielding material.