533 / 2022-03-28 20:10:44

Influence of PDDA-modified Nano-Al2O3 on the Properties of PMIA Insulating Paper

PMIA; PDDA; Nano-Al2O3; Interface characteristics; Insulation performance

In order to further improve the electrical insulation properties of meta-aramid paper, polydimethyldiallyl ammonium chloride (PDDA) was used for the modification of nano-Al₂O₃ in this work. The modified products were characterized by means of transmission electron microscopy (TEM), Fourier transform infrared spectrometer (FTIR) and liquid Zeta potential. The original and PDDA modified nano-Al₂O₃ was doped into the aramid fiber composite, and the effects of PDDA and filler mass fraction on several properties such as electrical conductivity, breakdown strength and surface charge dissipation rate of insulating paper were studied. The results showed that PDDA was successfully coated on the surface of nano-Al₂O₃, and its surface potential was changed from negative to positive, which could improve the interface characteristics between filler and matrix and enhance the dielectric strength of aramid paper. Besides, saturation effect of PDDA modification was observed, and when the amount of PDDA was 10% and the content of modified nano-Al₂O₃ was 3%, the breakdown strength of aramid paper was increased by 21%, and the volume conductivity was decreased by 68%.