Superior Flame Retardancy, Mechanical and Dielectric Properties of Epoxy Resin Composites Based on Molybdenum Disulfide-Melamine Trimetaphosphate Crystallite Composites

To improve the flame retardancy, mechanical and dielectric properties of epoxy resin (EP), promoting the application in aeronautic industry and other fields, molybdenum disulfide-melamine trimetaphosphate (MoS₂-MAP) crystallite composites are synthesized. The chemical, crystalline structure and thermal stabilities of MoS₂-MAPs are thoroughly characterized by Fourier transform infrared (FTIR), X-ray diffraction (XRD), scanning electron microscope (SEM), and thermo-gravimetric analysis (TGA) techniques, respectively. The morphologies of EP/MoS₂-MAP composites are assessed by SEM, thermal stability by TGA, fire retardancy by limiting oxygen index test (LOI), vertical burning standard test (UL-94), and cone calorimeter tests, mechanical properties by stress strain tests, and dielectric properties by impedance analyzer. Compared with pure EP, the mechanical, dielectrical properties, thermal stabilities and flame retardancy of EP/MoS₂-MAP composites can be significantly improved due to the good dispersibility of MoS₂ and MAP in matrix. While, the properties of EP/MoS₂-MAP composites can be further adjusted by controlling the mass raito of MoS₂ and MAP in MoS₂-MAP crystallite. EP with 4 wt% of MoS₂-MAP-50% (P content: 0.30%) shows the lowest dielectric constant and dielectric loss values on the basis of good flame retardancy and mechanical properties. The results show that the MoS₂-MAP crystallite composites can promote the application of EP composites in aeronautical devices, radar detection and other fields.