Abstract: A novel schiffbase monomer DP-1 was prepared via addition condensation with p-aminophenol and 1,4-phthaldiadehyde, based on which an liquid crystalline epoxy resin EP-1 was prepared. The structure of EP-1 was investigated by the Fourier transform infrared spectroscopy, nuclear magnetic resonance spectroscopy (1H-NMR), and differential scanning calorimetry. Using EP-1 as a toughener, 4,4’-diamino diphenyl sulfone (DDS) as a curing agent, cured epoxy system AG-80/EP-1/DDS was prepared. Testing of mechanical properties of the epoxy system showed that impact strength, bending strength, flexural modulus, and heat distortion temperature were 23.27 kJ/m2, 126.39 MPa, 414 GPa, and 232.5 ℃, respectively.

Key words: epoxy resin, liquid crystal, thoughening, heat resistance