Multilayered composite

Abstract

In accordance with certain embodiments of the present disclosure, a process for forming a multilayered electrospun composite is provided. The process includes forming a dispersion of polymeric nanofibers, a fiberizing polymer, and a solvent, the dispersion having a viscosity of at least about 50,000 cPs. Nanofibers from the dispersion are electrospun onto a first ePTFE layer. A second ePTFE layer is applied onto the nanofibers to form a composite structure. The composite structure is heated.

What is claimed is: 
     
         1 . A composite structure comprising a plurality of nanofibers on a first surface of a first polymeric layer. 
     
     
         2 . The composite structure of  claim 1 , wherein the nanofibers comprise one of polytetrafluoroethylene (PTFE), nylon, polyurethane, polyester, fluorinated ethylene propylene, or combinations thereof. 
     
     
         3 . The composite structure of  claim 1 , wherein the plurality of nanofibers is a plurality of spun nanofibers. 
     
     
         4 . The composite structure of  claim 3 , wherein the plurality of spun nanofibers is a plurality of electrospun nanofibers. 
     
     
         5 . The composite structure of  claim 1 , wherein the first polymeric layer is a first layer of expanded polytetrafluoroethylene (ePTFE) and wherein the composite structure further comprises a second ePTFE layer. 
     
     
         6 . The composite structure of  claim 5 , wherein the plurality of nanofibers are sandwiched between and bind together the first ePTFE layer and the second ePTFE layer. 
     
     
         7 . A stent, comprising:
 a first layer of polytetrafluoroethylene (PTFE) fibers disposed such that it defines an outside surface of the stent; and   a second layer of PTFE fibers disposed such that it defines an inside surface of the stent.   
     
     
         8 . The stent of  claim 7 , wherein the surface properties of at least one of the layers is modulated to manipulate cellular ingrowth and response. 
     
     
         9 . A composite structure comprising a tubular polymeric inner surface and a tubular polymeric outer surface, wherein at least one of the tubular polymeric inner surface and tubular polymeric outer surface comprises a plurality of polytetrafluoroethylene (PTFE) nanofibers. 
     
     
         10 . The composite structure of  claim 9 , wherein both the tubular polymeric inner surface and tubular polymeric outer surface comprise a plurality of PTFE nanofibers. 
     
     
         11 . The composite structure of  claim 10 , wherein the polytetrafluoroethylene (PTFE) nanofibers comprise spun polytetrafluoroethylene (PTFE) nanofibers. 
     
     
         12 . The composite structure of  claim 11 , wherein the spun polytetrafluoroethylene (PTFE) nanofibers comprise electrospun polytetrafluoroethylene (PTFE) nanofibers. 
     
     
         13 . The composite structure of  claim 9 , further comprising a substrate and one or more additional layers of polymeric material, wherein the one or more additional layers of polymeric material comprises a second plurality of polytetrafluoroethylene (PTFE) nanofibers. 
     
     
         14 . The composite structure of  claim 13 , wherein the one or more additional layers of polymeric material comprises a second plurality of electrospun polytetrafluoroethylene (PTFE) nanofibers. 
     
     
         15 . The composite structure of  claim 9 , wherein the PTFE nanofibers have a density such that there is a range of distances of about 0.1μ to about 50μ between points of contact of the nanofibers. 
     
     
         16 . The composite structure of  claim 9 , wherein the tubular polymeric inner surface and a tubular polymeric outer surface have different pore sizes.