Preparation and characterization of nano-Al_2O_3/PI trilayer composite films

GONG Guifen;XU Awen;ZHANG Liang;ZHANG Fan;LI Ze;School of Materials Science and Engineering, Harbin University of Science and Technology;

GONG Guifen%XU Awen%ZHANG Liang%ZHANG Fan%LI Ze%School of Materials Science and Engineering, Harbin University of Science and Technology

film;;nano-Al_2O_3;;polyimide;;electrospinning;;non-woven fabric

3,3′,4,4′-benzophenone tetracarboxylic dianhydride(BTDA) and 4,4′-diaminodiphenyl ether(ODA) were used as condensation monomers to prepare nano-Al_2O_3/PAA(polyamic acid) composite film by high-voltage electrospinning technology. Polyamic acid solution was prepared with pyromellitic dianhydride(PMDA) and 4,4′-diaminodiphenyl ether(ODA) as raw materials, and the film was cast and heated on both sides of the electrospun film. The chemical composition, microscopic morphology, corona resistance, mechanical properties and thermal properties of the composite film were tested and analyzed. The results show that the imidization of composite film is complete, and the nano-Al_2O_3 is uniformly dispersed in the polyimide matrix. When the nano-Al_2O_3 doping amount is 6% with the best overall performance, the corona aging time is 12.3 h, which is 3 times than that of undoped. The maximum tensile strength of the three-layer composite film is 174 MPa, while the elongation at break is also high up to 21%. The addition of nano-Al_2O_3 can improve the thermal stability of composite film, and the initial thermal decomposition temperature is increased from 578.7 ℃ to 591.3 ℃.