Polyarenazole microfilaments and process for making same

Abstract

Provided is a polymer filament having an average diameter of about 20 to 5000 nm, the filament comprising a polyarenazole polymer having an inherent viscosity of greater than about 20 g/dl. Also provided are yarns comprising such filaments. Additional aspects concern fabrics and garments comprising such filaments and/or yarns.

1 . A polymer filament having an average diameter of about 20 to 5000 nm, the filament comprising a polyarenazole polymer having an inherent viscosity of greater than about 20 g/dl. 
   
   
       2 . The polymer filament of  claim 1  wherein the average diameter is in the range of about 20 to 1000 nm. 
   
   
       3 . The polymer filament of  claim 2  wherein the average diameter is in the range of about 20 to 800 nm. 
   
   
       4 . The polymer filament of  claim 3  wherein the average diameter is in the range of about 100 to 500 nm. 
   
   
       5 . The polymer filament of  claim 1  wherein the polyarenazole polymer has an inherent viscosity of greater than about 25 g/dl. 
   
   
       6 . The polymer filament of  claim 1  wherein the polyarenazole polymer is a polypyridoazole polymer. 
   
   
       7 . The polymer filament of  claim 6  wherein the polypyridoazole polymer is poly[2,6-diimidazo[4,5-b:4,5-e]-pyridinylene-1,4-(2,5-dihydroxy)phenylene). 
   
   
       8 . A yarn comprising a polyarenazole filament having an average diameter of about 20 to 5000 nm and a filament tenacity of greater than about 10 g/denier. 
   
   
       9 . The yarn of  claim 8  wherein the polyarenazole filament comprises polypyridoazole polymer. 
   
   
       10 . The yarn of  claim 9  wherein the polypyridoazole is poly[2,6-diimidazo[4,5-b:4,5-e]-pyridinylene-1,4-(2,5-dihydroxy)phenylene). 
   
   
       11 . A fabric comprising filament of  claim 1 . 
   
   
       12 . A garment comprising fabric of  claim 11 . 
   
   
       13 . A method of producing a polyarenazole polymer filament comprising:
 extruding a solution comprising polyarenazole polymer through a spinneret having a first applied voltage; and   collecting the extruded polyarenazole polymer on a collection surface optionally having a second applied voltage that is opposite in polarity to the first applied voltage.   
   
   
       14 . The method of  claim 13  wherein the solution comprising polyarenazole polymer comprises polyphosphoric acid as a solvent. 
   
   
       15 . The method of  claim 13  wherein the first applied voltage is in the range of 1 kV to 300 kV. 
   
   
       16 . The method of  claim 13  wherein the second applied voltage is in the range of 0 to 10 kV. 
   
   
       17 . The method of  claim 13  wherein the polyarenazole polymer is poly[2,6-diimidazo[4,5-b:4,5-e]-pyridinylene-1,4-(2,5-dihydroxy)phenylene). 
   
   
       18 . The method of  claim 13  wherein the method additionally comprises the step of passing the extruded polyarenazole polymer solution through an air gap. 
   
   
       19 . The method of  claim 18  wherein the method additionally comprises the step of accelerating the extruded polymer solution in the air gap by providing air flow along the direction between the spinneret and collection surface. 
   
   
       20 . The method of  claim 19  where the second applied voltage is zero.