Patent ID: 8257641

Claim:
A method of forming core-sheath nanofibers by coaxial electrospinning comprising: providing a core solution comprising a high performance polymer selected from the group consisting of an organic polymer, an inorganic polymer, and combinations thereof; providing a sheath solution comprising a solvent-insoluble fluororesin, a sacrificial polymeric binder, and solvent; coaxial electrospinning the core and sheath solutions to form a plurality of core-sheath polymer nanofibers, wherein the core solution forms a polymer core and the sheath solution forms a polymer sheath surrounding the core; heating the core-sheath nanofibers to a first temperature ranging, from about 100° C. to about 280° C.; and heating the core-sheath nanofibers to a second temperature ranging from about 285° C. to about 380° C.