Preparation and characterization of Polyimide/Al₂O₃ nanocomposite film with good corona resistance

Abstract

Polyimide/Al2O3 (PI/Al2O3) nanocomposite films based on pyromellitic dianhydride and 4,4 0 -oxydianiline were fabricated by adding different proportions of nanoAl 2 O 3 inorganic particles via in situ polymerization. Microstructural analysis by scanning electron microscope (SEM) showed that the inorganic particles were homogenously dispersed in the PI matrix when mixed with appropriate amount of nano-Al 2 O 3 . Fourier transform infrared spectroscopy and X-ray diffraction analysis were also used to investigate the effect of nanoAl 2 O 3 on the polymerization process. The obtained composite films and pure film were characterized by thermogravimetry analysis, and the experimental results indicated that when comparing with pure film, the nanocomposite films displayed a better thermal stability than the pure one. Moreover, results also showed that the thermal stability of composite films steadily improved with increased content of nanoAl 2 O 3 particle. The electrical property test demonstrated that the composite films performed improving electrical breakdown strength and corona resistance. The microstructure changes of pure film and PI/Al 2 O 3 nanocomposite films during corona aging have been analyzed by SEM. POLYM. COMPOS., 37:763-770, 2016.

Fabrication, Morphology and Properties of Polyimide/Al₂O₃ Nanocomposite Films via Surface Modification and Ion-Exchange Technique

“…The above results indicate that the thermal stability of pristine PI film could be improved by introducing Al 2 O 3 [16] . The electrical breakdown strength is a key parameter that is widely used to measure the insulating capability of the dielectrics, because breakdown would cause a short circuit, which could be a fatal malfunction for power equipment [1,2,4,6,14] . Fig.…”

“…Polyimide (PI) films have gained considerable importance as high-performance polymers and matrices, which have been widely used in microelectronic and electrical industries [1][2][3][4][5][6][7][8] . On the other hand, better quality is still needed in current advanced microelectronic and electrical applications.…”

“…For example, the cycle life of insulations of induction motors fed by pulse width modulation (PWM) converters is often reduced to 1/10-1/20, and breakdown occurs only after one or two years' use [1,[9][10][11][12][13][14] . Therefore, Polyimide composite materials that combine PI with metals oxide is one of the best choices in the past few years because of their dramatic improvements in mechanical properties, thermal stabilities and electric breakdown strength compared to their pristine state [1,2,[8][9][10][11] . Among the inorganic particles used, Al 2 O 3 is often chosen as filler to improve the insulation properties of polymer materials.…”

“…Among the inorganic particles used, Al 2 O 3 is often chosen as filler to improve the insulation properties of polymer materials. PI/Al 2 O 3 composites have traditionally been prepared by mixing alumina oxide with a polymer solution followed by curing [1,11,15] . These processes, however, often lead to an inhomogeneous dispersion and an uncontrollable size distribution of Al 2 O 3 particles.…”

High Electrical and Mechanical Properties Obtained in a Polyimide‐Based Nanocomposite with Sandwich Structure via Multidimensional Design

“…), inorganic nanomaterials (TiO 2 , [ 13 ] TiC, [ 14 ] ZnO, [ 15 ] BN, [ 5 ] AlN, [ 16 ] MoS 2 , [ 17 ] graphene, [ 6 ] carbon nanotubes, [ 18 ] MXene, [ 7 ] montmorillonite, [ 19 ] etc. ), ceramic nanomaterials (BaTiO 3 , [ 20 ] SrTiO 3 , [ 21 ] CaCu 3 Ti 4 O 12 , [ 22 ] SiO 2 , [ 23 ] SiC, [ 24 ] Al 2 O 3 , [ 25 ] MgO, [ 26 ] MnO, [ 27 ] etc. ), metal–organic framework materials, [ 28 ] etc.…”