abstract |
The present invention is directed to a process for electrostatically spinning fibers of polyamic acid and the fibers thus produced as well as the nonwoven webs that may be formed from the fibers. According to the processes of the present invention, polyamic acid solutions may be electrostatically spun to form fibers of very small diameter, such as, for instance, less than about 5 μm in average diameter. The fibers may be formed into a nonwoven web having very high specific surface area and large porosity. The polyamic acid may be converted to polyimide to form a polyimide nonwoven web. The polyimide nonwoven web may then be activated through a carbonization process to enhance the electrochemical properties of the web. The nonwoven webs of the invention may be utilized in a variety of electrochemical applications including, for example, electrical double layer capacitors. |