Abstract
Epoxy resin has been wide applied in aerospace, superconducting industries because of the high electrical insulation, excellent adhesive properties and great chemical resistance. In this paper, epoxy/AlN composites were prepared by changing the content of the flexible amine (D-230) and the diethyl toluene diamine (DETDA) from 0 to 100 wt%. The effects of different ratios of D-230 and DETDA were investigated on the mechanical and dielectric properties of epoxy/AlN composites at liquid nitrogen temperature (77 K) and room temperature (RT). The properties of the samples were characterized by flourier transformed infrared (FTIR), scanning electron microscopy and broadband dielectric spectrometer. FTIR results showed that AlN particles were successfully modified by the silane coupling agent (KH-560). Tensile testing showed that the addition of flexible diamines generally improved the elongation at break at both RT and 77 K and the tensile strength at 77 K. The introduction of D-230 led to a lower dielectric constant at cryogenic temperature than that at RT.