CONTINUOUS PRODUCTION PROCESS FOR POLYTETRAFLUOROETHYLENE FUNCTIONAL FILM FOR ELECTRO-MECHANICAL ENERGY CONVERSION

The present invention relates to a continuous production process for a polytetrafluoroethylene functional film for electro-mechanical energy conversion, comprising two steps of thermal bonding a composite film having a microporous structure and electrically charging the composite film, wherein the step of thermal bonding a composite film having a microporous structure consists in: providing at least two layers of dense polytetrafluoroethylene film with one layer of porous polytetrafluoroethylene film sandwiched between every two adjacent layers of polytetrafluoroethylene film, alternately laminating and following by introducing same between an upper and a lower thermal press roller for thermal pressure bonding, so as to produce the composite film; and then electrically charging the composite film to obtain a polytetrafluoroethylene piezoelectric electret film. The step of electrically charging the composite film consists in: corona-polarizing the composite film by introducing the composite film between an electrode roller and a corona electrode, or introducing the composite film into an electroplating region and attaching electrodes to the upper and lower surfaces thereof, followed by introducing the film to a charging region by a contacting process. The advantages are: the production process of the present invention has continuity, high productivity, and the products of polytetrafluoroethylene functional films for electro-mechanical energy conversion exhibit excellent piezoelectric performance and high thermal stability.