Electrospun doped nanofibers and process of preparation thereof

Abstract

This invention is directed to nanofibers doped with an alkali salt having improved tensile properties, and process of preparation thereof.

What is claimed: 
     
         1 . A nanofiber comprising a polymer doped with alkali salt, wherein said nanofiber has improved mechanical properties. 
     
     
         2 . The nanofiber of  claim 1 , wherein said polymer is polymethyl methacrylate (PMMA), polyvinyl alcohol, polyethylene oxide, polyurethane, a polyamide, poly(vinyl chloride) or any combination thereof. 
     
     
         3 . The nanofiber of  claim 1 , wherein said alkali salt is sodium chloride (NaCl). 
     
     
         4 . The nanofiber of  claim 1 , wherein said polymer is polymethyl methacrylate (PMMA) and said salt is NaCl. 
     
     
         5 . The nanofiber of  claim 1 , wherein said alkali salt is between about 0.2-0.4% weight percentage from said polymer. 
     
     
         6 . The nanofiber of  claim 1 , wherein said mechanical properties are stiffness, strength, toughness or any combination thereof. 
     
     
         7 . The nanofiber of  claim 5 , wherein said strength is improved by between about 75-100%. 
     
     
         8 . The nanofiber of  claim 1 , wherein the diameter of said nanofiber is between 200 nm to 1 micron 
     
     
         9 . A process for the preparation of an electrospun nanofiber having improved mechanical properties comprising: (a) preparing a solution or a melt of an alkali salt and a polymer; (b) adding said solution or melt to an electrospinning system; (c) applying an electric field to yield liquid jets which are collected as fibers by a grounded collecting plate. 
     
     
         10 . The process of  claim 9 , wherein said polymer is polymethyl methacrylate (PMMA), polyvinyl alcohol, polyethylene oxide, polyurethane, a polyamide, poly(vinyl chloride) or any combination thereof. 
     
     
         11 . The process of  claim 9 , wherein said alkali salt is sodium chloride (NaCl). 
     
     
         12 . The process of  claim 9 , wherein said polymer is polymethyl methacrylate (PMMA) and said salt is NaCl. 
     
     
         13 . The process of  claim 9 , wherein said alkali salt is in between about 0.2-0.4% weight percentage from said polymer. 
     
     
         14 . The process of  claim 9 , wherein said mechanical properties are stiffness, strength, toughness or combination thereof. 
     
     
         15 . The process of  claim 14 , wherein said strength is improved by between about 75-100%. 
     
     
         16 . The process of  claim 9 , wherein the diameter of said nanofiber is between 200 nm to 1 micron. 
     
     
         17 . The process of  claim 9 , wherein said electric field is between 50-100 kV/m. 
     
     
         18 . The process of  claim 9 , wherein said collected fibers were further treated with methanol. 
     
     
         19 . A rope having improved mechanical properties comprising said nanofiber of  claim 1 ; wherein said mechanical properties are stiffness, strength, toughness or any combination thereof. 
     
     
         20 . A cable having improved mechanical properties comprising said nanofiber of  claim 1 , wherein said improved mechanical properties are stiffness, strength, toughness or any combination thereof.