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In this study, a straightforward and cost-effective method for making nonwoven membranes of polyimide using as insulation materials was described. Poly (amic acid) (PAA), a precursor of polyimide, was synthesized from 4, 4'-oxydiphthalic anhydride (ODPA) and 4, 4'-oxydianiline (ODA) at room temperature for about 4h. ODPA-ODA polyimide (PI) non-woven membranes were prepared by electrospinning the PAA solution followed by thermal imidization. The surface morphology, crystallinity of PAA and ODPA-ODA PI were characterized by Scanning Electron Microscope (SEM) and X-ray diffraction (XRD) respectively. The mechanical properties of ODPA-ODA PI membranes were performed using Electron Universal Testing Machine. The result indicated that the diameter of fibers of ODPA-ODA PI obtained after imidization at 300°C could decrease in size by 500nm and exhibited shrunken, twisted and ribbon-shaped structure.Electrospinning is being used to an increasing extent to produce ultra thin fibers from a wide range of polymer materials /1-5/. In electrospinning, the