Electrospinning Process

Abstract

A method for electrospinning polymer fibers and the resultant electrospun fibers are disclosed. In the electrospinning method, the polymer undergoes a crosslinking reaction prior to and during the electrospinning process.

1 . A method for electrospinning a fiber from an electrically conducting solution of polymer in the presence of an electric field between a spinneret and a ground source, the polymer undergoing a crosslinking reaction prior to and during electrospinning. 
   
   
       2 . The method of  claim 1  in which the polymer contains crosslinkable groups along the polymer backbone. 
   
   
       3 . The method of  claim 2  in which the crosslinkable groups are reactive with moisture. 
   
   
       4 . The method of  claim 3  in which the crosslinkable groups are silane groups. 
   
   
       5 . The method of  claim 2  in which the polymer is a (meth)acrylic polymer. 
   
   
       6 . The method of  claim 2  in which the polymer is a (meth)acrylic polymer containing silane groups. 
   
   
       7 . The method of  claim 2  in which the polymer, besides containing crosslinkable groups, also contains groups selected from carboxyl and hydroxyl. 
   
   
       8 . The method of  claim 2  in which the polymer contains silane groups, carboxyl groups, hydroxyl groups and nitrogen-containing groups. 
   
   
       9 . The method of  claim 2  in which the silane groups are present in the polymer in amounts of 0.2 to 20 percent by weight silicon based on total polymer weight. 
   
   
       10 . The method of  claim 8  in which the polymer contains from:
 (a) 0.2 to 20 percent silane group measured as silicon,   (b) 1 to 45 percent carboxyl groups,   (c) 0.5 to 6.5 percent hydroxyl groups, and   (d) 0.2 to 5.0 percent nitrogen groups;   
     the percentages by weight being based on total polymer weight. 
   
   
       11 . The method of  claim 1  in which the solution contains a thickener. 
   
   
       12 . The method of  claim 11  in which the thickener is polyvinyl pyrrolidone. 
   
   
       13 . The method of  claim 12  in which the polyvinyl pyrrolidone is present in amounts of no greater than 20 percent by weight based on total weight of solution. 
   
   
       14 . An electrospun fiber comprising a polymer that has been crosslinked prior to and during the electrospinning process. 
   
   
       15 . The electrospun fiber of  claim 14  having a diameter of from 5 to 5,000 nanometers. 
   
   
       16 . The electrospun fiber of  claim 14  having —Si—O—Si— crosslinks. 
   
   
       17 . The electrospun fiber of  claim 14  being a crosslinked (meth)acrylic polymer. 
   
   
       18 . The electrospun fiber of  claim 14  being a (meth)acrylic polymer with —Si—O—Si— crosslinks.