The invention discloses heat-resistant modified
epoxy resin and a preparation method thereof, and belongs to the technical field of
high polymer materials. The heat-resistant modified
epoxy resin is prepared from the following components in parts by
mass: 45 to 55 parts of matrix
epoxy resin, 10 to 20 parts of methyl phenyl
silicone resin, 8 to 12 parts of
nano silicon dioxide, 0.8 to 2.0 parts of a
silane coupling agent, 6 to 10 parts of a curing agent, 0.3 to 0.8 part of an
accelerant, 15 to 30 parts of
silica fume powder and 0.5 to 1.2 parts of an
antioxidant. By introducing components such as methyl phenyl
silicone resin and
nano silicon dioxide with a specific particle size, and combining the synergistic effect of the
silane coupling agent, the
heat resistance of the epoxy resin is effectively improved; the
antioxidant with a specific structure is used, and the performance
retention rate of the modified epoxy resin under a thermo-oxidative aging condition is remarkably improved, so that the service life of the material is prolonged, and the long-term stability of the material in a high-temperature environment is enhanced.