Method of Spinning Conductive Poly(3,4-Ethylenedioxythiophene): Polystyrene Sulfonate Fibers

Abstract

A method of producing poly (3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) fibers includes the step of extruding a PEDOT:PSS dope through a spinneret into a coagulation bath of a non-solvent to PEDOT:PSS polymer to produce an individual filament that floats to an upper surface of the coagulation bath. The non-solvent to PEDOT:PSS polymer has a boiling point less than 125° C. and a density higher than the PEDOT:PSS nascent filament. The individual filament is dried and then contacted with other dried filaments to make a multifilament tow.

What is claimed: 
     
         1 . A method of spinning conductive poly (3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) fibers, comprising:
 extruding a PEDOT:PSS dope through a spinneret into a coagulation bath of formic acid to produce an individual filament that floats to an upper surface of the coagulation bath.   
     
     
         2 . The method of  claim 1 , further including extruding the PEDOT:PSS dope upward into the coagulation bath of formic acid. 
     
     
         3 . The method of  claim 2 , further including removing the individual filament from the upper surface of the coagulation bath of formic acid by pulling upward onto a guide surface. 
     
     
         4 . The method of  claim 3 , further including pulling the individual filament from the guide surface into the air. 
     
     
         5 . The method of  claim 4 , further including drying the individual filament after the pulling from the guide surface. 
     
     
         6 . The method of  claim 5 , further including contacting the individual filament with other PEDOT:PSS filaments only after the individual filament and the other PEDOT:PSS filaments have been dried. 
     
     
         7 . The method of  claim 6 , further including forming and collimating a tow of PEDOT:PSS fibers from the dried individual filament and the other dried PEDOT:PSS filaments to provide a multifilament tow of PEDOT:PSS fibers. 
     
     
         8 . The method of  claim 7 , further including taking up the tow of PEDOT:PSS fibers on the surface of a rotating cylindrical core. 
     
     
         9 . The method of  claim 8 , wherein the drying of the individual filament is by subjecting the individual filament to a column of heated air that quickly evaporates the formic acid. 
     
     
         10 . The method of  claim 1 , wherein the PEDOT:PSS dope has about 1:2.5 PEDOT:PSS weight ratio. 
     
     
         11 . The method of  claim 10 , wherein the PEDOT:PSS dope has a solids concentration of about 2.5 wt. %. 
     
     
         12 . The method of  claim 1 , wherein the coagulation bath of formic acid has a concentration greater than 85%. 
     
     
         13 . The method of  claim 1 , wherein the spinneret includes at least one capillary having a diameter of about 100 μm and a length to diameter of L/D=5. 
     
     
         14 . A method of producing poly (3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) fibers, comprising:
 extruding a PEDOT:PSS dope through a spinneret into a coagulation bath of a non-solvent to PEDOT:PSS polymer to produce an individual filament that floats to an upper surface of the coagulation bath wherein the non-solvent to PEDOT:PSS polymer has a boiling point of less than 125° C. and a density higher than the PEDOT:PSS nascent filament.   
     
     
         15 . The method of  claim 14 , further including extruding the PEDOT:PSS dope upward into the coagulation bath. 
     
     
         16 . The method of  claim 15 , further including removing the individual filament from the upper surface of the coagulation bath onto a guide surface. 
     
     
         17 . The method of  claim 16 , further including removing the individual filament from the guide surface into the air. 
     
     
         18 . The method of  claim 17 , further including drying the individual filament after the removing from the guide surface. 
     
     
         19 . The method of  claim 18 , further including forming and collimating a tow of PEDOT:PSS fibers from the dried individual filament and the other dried PEDOT:PSS filaments to provide a multifilament tow of PEDOT:PSS fibers. 
     
     
         20 . A method of producing poly (3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) fibers, comprising forming a multifilament PEDOT:PSS fiber tow by upward solution spinning of a PEDOT:PSS dope in a formic acid-based coagulation bath.