Nanobubbles for preparation of spun fibrous materials

Abstract

Provided herein are methods that involve the use of nanobubbles for preparing spun fibers. One such method includes (a) introducing a first dope fluid comprising a first polymer into a first opening of a spinneret; and (b) extruding a fiber jet comprising the first polymer from the spinneret, optionally into a coagulation bath comprising a fiber-forming coagulation medium, to form the fiber; wherein the first dope fluid, and optionally the coagulation bath, comprises nanobubbles.

What is claimed is: 
     
         1 . A method of forming a fiber comprising:
 (a) introducing a first dope fluid comprising a first polymer into a first opening of a spinneret; and   (b) extruding a fiber jet comprising the first polymer from the spinneret into a coagulation bath comprising a fiber-forming coagulation medium to form a fiber,   wherein the first dope fluid, the coagulation bath, or both comprise nanobubbles.   
     
     
         2 . The method of  claim 1 , wherein the first dope fluid comprises a composition in which the first polymer is dissolved or dispersed in a solvent selected from the group consisting of aqueous solvents, organic solvents, and combinations thereof. 
     
     
         3 . The method of  claim 2 , further comprising at least partially evaporating the solvent after extruding the fiber jet from the spinneret and before introducing the fiber jet into the coagulation bath. 
     
     
         4 . The method of  claim 1 , wherein the first dope fluid comprises a flowable polymer. 
     
     
         5 . The method of  claim 1 , further comprising introducing a second dope fluid comprising a second polymer into a second opening of the spinneret and extruding a fiber jet comprising the first polymer and the second polymer from the spinneret into the coagulation bath to form a composite fiber comprising a first layer comprising the first polymer and a second layer comprising the second polymer in which the first and second layers are in a coaxial arrangement, wherein the dope fluid, the second dope fluid, coagulation bath, or combination thereof comprise nanobubbles. 
     
     
         6 . The method of  claim 1 , further comprising contacting the fiber with a second dope fluid comprising a second polymer to form a composite fiber comprising a first layer comprising the first polymer and a second layer comprising the second polymer in which the first and second layers are in a coaxial arrangement, wherein the first dope fluid, the second dope fluid, coagulation bath, or combination thereof comprise nanobubbles. 
     
     
         7 . The method of  claim 1 , further comprising introducing a bore fluid comprising an aqueous solvent, organic solvent, or combination thereof into a second opening of the spinneret; extruding a fiber jet comprising the first polymer and the bore fluid from the spinneret; and removing the bore fluid to form a hollow fiber, wherein the first dope fluid, the bore fluid, coagulation bath, or combination thereof comprise nanobubbles. 
     
     
         8 . A method of forming a fiber comprising:
 (a) introducing a first dope fluid comprising a first polymer into a first opening of a spinneret; and   (b) extruding a fiber jet comprising the first polymer from the spinneret to form a fiber,   wherein the first dope fluid comprises nanobubbles.   
     
     
         9 . The method of  claim 8 , wherein the first dope fluid comprises a composition in which the first polymer is dissolved or dispersed in a solvent selected from the group consisting of aqueous solvents, organic solvents, and combinations thereof. 
     
     
         10 . The method of  claim 9 , further comprising removing the solvent by contacting the fiber jet with a heated roller. 
     
     
         11 . The method of  claim 9 , further comprising removing the solvent by introducing the fiber jet into a heated gas chamber. 
     
     
         12 . The method of  claim 8 , wherein the first dope fluid comprises a flowable polymer. 
     
     
         13 . The method of  claim 8 , further comprising introducing a second dope fluid comprising a second polymer into a second opening of the spinneret; and extruding a fiber jet comprising the first polymer and the second polymer from the spinneret to form a composite fiber comprising a first layer comprising the first polymer and a second layer comprising the second polymer in which the first and second layers are in a coaxial arrangement, wherein the first dope fluid, the second dope fluid, or combination thereof comprise nanobubbles. 
     
     
         14 . The method of  claim 8 , further comprising contacting the fiber with a second dope fluid comprising a second polymer to form a composite fiber comprising a first layer comprising the first polymer and a second layer comprising the second polymer in which the first and second layers are in a coaxial arrangement, wherein the first dope fluid, the second dope fluid, or combination thereof comprise nanobubbles. 
     
     
         15 . The method of  claim 8 , further comprising introducing a bore fluid comprising an aqueous solvent, organic solvent, or combination thereof into a second opening of the spinneret; extruding a fiber jet comprising the first polymer and the bore fluid from the spinneret, and removing the bore fluid to form a hollow fiber, wherein the first dope fluid, the bore fluid, or combination thereof comprise nanobubbles. 
     
     
         16 . The method of  claim 9 , further comprising providing a collector for collecting fibers from the spinneret and creating an electrostatic field between the spinneret and collector by applying a high voltage to the spinneret while grounding the collector.