In order to improve the corona resistanceproperties of polyesterimide resin

nanoAl2O3 sol was prepared by microemulsionhydrothermalmethod and dispersed into polyesterimide resin solution by mechanical blending

then nanoAl2O3 hybrid polyesterimide composite material was prepared Theresults show that the nanoparticles are dispersed in the polyesterimide matrix;With the increase of doping amount

the corona resistance of the compositesincreases

but the dielectric strength decreases; When the doping amount was12%

its coronaresistant life is 5 times more than pure polyesterimide resin

and the dielectric strength is 1752kV/mmWith the increase of the doping amount

the dielectric loss of the material is little affected

but the dielectriccoefficient increases slightly The nanoAl2O3 particles in matrix have littleeffect on the heat resistance of the material