Melt Electrospun Fibers Containing Micro and Nanolayers and Method of Manufacturing

Abstract

Fibers having two or more alternating polymer layers are formed by co-extrusion followed by electroprocessing. The fibers can be used as a non-woven mat or other substrate for a variety of applications. Delamination of the fibers using ultrasonication yields separated, micro and nanolayer, fiber ribbons which may also be used a non-woven mat or other substrate.

1 . A co-extruded, electroprocessed fiber containing a plurality of alternating layers of two or more different polymers, wherein said fiber has a diameter of 50 μm or less and has at least 50 layers. 
     
     
         2 . The co-extruded, electroprocessed fiber of  claim 1  wherein said fiber has a diameter of 10 μm or less. 
     
     
         3 . A fibrous substrate, comprising a plurality of co-extruded, electroprocessed fibers containing a plurality of alternating layers of two or more different polymers, wherein said fiber has a diameter of 50 μm or less and has at least 50 layers. 
     
     
         4 . The fibrous substrate of  claim 3  wherein said co-extruded, electroprocessed fibers have a diameter of 10 μm or less. 
     
     
         5 . The fibrous substrate of  claim 3  configured as a non-woven. 
     
     
         6 . The fibrous substrate of  claim 3  further comprising a bioactive agent deposited on said substrate. 
     
     
         7 . The fibrous substrate of  claim 3  further comprising a catalytic agent deposited on said substrate. 
     
     
         8 . The fibrous substrate of  claim 3  further comprising a fire or flame retardant deposited on said substrate. 
     
     
         9 . A fibrous substrate, produced by the process of:
 co-extruding two or more polymers;   electroprocessing the co-extruded polymers to produce a fiber containing a plurality of alternating layers of two or more different polymers, wherein said fiber has a diameter of 50 μm or less; and   delaminating the fiber to yield fiber ribbons of individual polymers co-extruded in said co-extruding step.   
     
     
         10 . The fibrous substrate of  claim 9  wherein said delaminating step is performed by sonication of said fiber. 
     
     
         11 . The fibrous substrate of  claim 9  configured as a non-woven. 
     
     
         12 . The fibrous substrate of  claim 9  further comprising a bioactive agent deposited on said substrate. 
     
     
         13 . The fibrous substrate of  claim 9  further comprising a catalytic agent deposited on said substrate. 
     
     
         14 . The fibrous substrate of  claim 9  further comprising a fire or flame retardant deposited on said substrate. 
     
     
         15 . A method of producing ribbon shaped fibers or a fibrous substrate which includes ribbon shaped fibers, comprising the steps of:
 co-extruding two or more polymers;   electroprocessing the co-extruded polymers to produce a fiber containing a plurality of alternating layers of two or more different polymers, wherein said fiber has a diameter of 50 μm or less; and   delaminating the fiber to yield fiber ribbons of individual polymers co-extruded in said co-extruding step.   
     
     
         16 . The method of  claim 15  wherein said delaminating step is performed by sonication of said fiber. 
     
     
         17 . The method of  claim 15  wherein said electroprocessing and delaminating steps are performed under conditions which produce a fibrous substrate configured as a non-woven. 
     
     
         18 . The method of  claim 15  further comprising depositing a bioactive agent on said fiber ribbons. 
     
     
         19 . The method of  claim 15  further comprising depositing a catalytic agent on said fiber ribbons. 
     
     
         20 . The method of  claim 15  further comprising depositing a fire or flame retardant on said fiber ribbons. 
     
     
         21 . The method of  claim 15  wherein said fiber produced in said electroprocessing step has a diameter of 10 μm or less. 
     
     
         22 . The method of  claim 15  wherein said fiber produced in said electroprocessing step has at least three layers. 
     
     
         23 . The method of  claim 15  wherein said fiber produced in said electroprocessing step has at least 50 layers. 
     
     
         24 . A method of producing fibers or a fibrous substrate which includes said fibers, comprising the steps of:
 co-extruding two or more polymers; and   electroprocessing the co-extruded polymers to produce a fiber containing a plurality of alternating layers of two or more different polymers, wherein said fiber has a diameter of 50 μm or less.   
     
     
         25 . The method of  claim 24  wherein said fiber produced in said electroprocessing step has a diameter of 10 μm or less. 
     
     
         26 . The method of  claim 24  wherein said fiber produced in said electroprocessing step has at least three layers. 
     
     
         27 . The method of  claim 24  wherein said fiber produced in said electroprocessing step has at least 50 layers.