Durable high strength polymer composites suitable for prosthetic valves

Abstract

Thin, biocompatible, high-strength, composite materials are disclosed that are suitable for use in a valve for regulating blood flow direction. In one aspect, the composite material maintains flexibility in high-cycle flexural applications, making it particularly applicable to high-flex implants such as a prosthetic heart valve leaflet. The composite material includes a porous polymer membrane and an elastomer or elastomeric material, wherein the elastomer or elastomeric material fills substantially all of the pores of the porous polymer membrane.

What is claimed is: 
     
         1 . A valve, comprising:
 at least one leaflet operable to move between open and closed positions, each leaflet including a composite material comprising a synthetic polymer membrane and an elastomer or elastomeric material, the synthetic polymer membrane comprising fibers that define space therebetween defining pores, wherein a diameter of a majority of the fibers is less than about 1 μm, the elastomer or elastomeric material being disposed in substantially all of the pores.   
     
     
         2 . The valve of  claim 1 , wherein the composite material further includes a layer of one of the elastomer or elastomeric material. 
     
     
         3 . The valve of  claim 1 , wherein the composite material comprises elastomer or elastomeric material by weight in a range from about 10% to about 90%. 
     
     
         4 . The valve of  claim 1 , wherein the elastomer or elastomeric material is a TFE/PMVE (tetrafluoroethylene-perfluoromethylvinyl ether) copolymer. 
     
     
         5 . The valve of  claim 4 , wherein the TFE/PMVE copolymer consists essentially of between about 40 and 80 weight percent perfluoromethyl vinyl ether and complementally 60 and 20 weight percent tetrafluoroethylene. 
     
     
         6 . The valve of  claim 1 , wherein the elastomer or elastomeric material is a fluoroelastomer. 
     
     
         7 . The valve of  claim 1 , wherein the elastomer or elastomeric material is selected from the group consisting of TFE/PMVE (tetrafluoroethylene-perfluoromethylvinyl ether) copolymer, TFE-PAVE (tetrafluoroethylene-perfluoro (alkyl vinyl ether)) copolymer, FEP (fluorinated ethylene propylene), fluoroelastomers, silicones, and urethanes. 
     
     
         8 . The valve of  claim 1 , wherein the synthetic polymer membrane is a porous fluoropolymer membrane. 
     
     
         9 . The valve of  claim 8 , wherein the porous fluoropolymer membrane has a matrix tensile strength in at least one direction greater than about 150 MPa. 
     
     
         10 . The valve of  claim 1 , wherein the synthetic polymer membrane is porous polyethylene membrane. 
     
     
         11 . The valve of  claim 10 , wherein the porous polyethylene membrane has a matrix tensile strength in at least one direction greater than about 150 MPa. 
     
     
         12 . The valve of  claim 1 , wherein the leaflet has a thickness of less than about 350 μm. 
     
     
         13 . The valve of  claim 1 , wherein the pores have a pore size that is less than about 5 μm. 
     
     
         14 . The valve of  claim 1 , wherein the pores have a pore size that is less than about 1 μm. 
     
     
         15 . The valve of  claim 1 , wherein the pores have a pore size that is less than about 0.1 μm. 
     
     
         16 . The valve of  claim 1 , wherein the diameter of a majority of the fibers is less than about 0.1 μm. 
     
     
         17 . The valve of  claim 1 , wherein the synthetic polymer membrane comprises substantially only of fibers. 
     
     
         18 . The valve of  claim 1 , further comprising a support structure, the at least one leaflet being supported on the support structure and movable between open and closed positions. 
     
     
         19 . The valve of  claim 18 , wherein the support structure is selectively diametrically adjustable for endovascular delivery and deployment at a treatment site. 
     
     
         20 . The valve of  claim 1 , wherein the synthetic polymer membrane is expanded fluoropolymer membrane, wherein the elastomer or elastomeric material is a TFE/PMVE copolymer, and wherein the valve is operable to be a prosthetic heart valve. 
     
     
         21 . A valve, comprising:
 at least one leaflet operable to move between open and closed positions, each leaflet including a composite material comprising a synthetic polymer membrane having a plurality of pores and an elastomer or elastomeric material present in substantially all of the pores, the composite material comprising elastomer or elastomeric material by weight in a range from about 10% to about 90%.   
     
     
         22 . The valve of  claim 21 , wherein the composite material comprises less than about 70% synthetic polymer membrane by weight. 
     
     
         23 . The valve of  claim 21 , wherein the composite material comprises less than about 60% synthetic polymer membrane by weight. 
     
     
         24 . The valve of  claim 21 , wherein the composite material comprises less than about 50% synthetic polymer membrane by weight. 
     
     
         25 . The valve of  claim 21 , wherein the composite material further includes a layer of one of either the elastomer or elastomeric material. 
     
     
         26 . The valve of  claim 21 , wherein the synthetic polymer membrane is a porous fluoropolymer membrane. 
     
     
         27 . The valve of  claim 26 , wherein the porous fluoropolymer membrane has a matrix tensile strength in at least one direction greater than about 150 MPa. 
     
     
         28 . The valve of  claim 21 , wherein the synthetic polymer membrane is porous polyethylene membrane. 
     
     
         29 . The valve of  claim 28 , wherein the porous polyethylene membrane has a matrix tensile strength in at least one direction greater than about 150 MPa. 
     
     
         30 . The valve of  claim 21 , wherein the pores are defined by a fibrous structure comprising fibers that have an average fiber diameter of less than about 1 μm. 
     
     
         31 . The valve of  claim 21 , wherein the pores are defined by a fibrous structure comprising fibers that have an average fiber diameter of less than about 0.1 μm. 
     
     
         32 . The valve of  claim 21 , wherein the elastomer or elastomeric material is a fluoroelastomer. 
     
     
         33 . The valve of  claim 21 , wherein the elastomer or elastomeric material is a TFE/PMVE (tetrafluoroethylene-perfluoromethylvinyl ether) copolymer. 
     
     
         34 . The valve of  claim 33 , wherein the TFE/PMVE copolymer consists essentially of between about 40 and 80 weight percent perfluoromethyl vinyl ether and complementally 60 and 20 weight percent tetrafluoroethylene. 
     
     
         35 . The valve of  claim 21 , wherein the elastomer or elastomeric material is selected from the group consisting of TFE/PMVE (tetrafluoroethylene-perfluoromethylvinyl ether) copolymer, TFE-PAVE (tetrafluoroethylene-perfluoro (alkyl vinyl ether)) copolymer, FEP (fluorinated ethylene propylene), fluoroelastomers, silicones, and urethanes. 
     
     
         36 . The valve of  claim 21 , wherein the leaflet has a thickness of less than about 350 μm. 
     
     
         37 . The valve of  claim 21 , wherein the pores have a pore size that is less than about 5 μm. 
     
     
         38 . The valve of  claim 21 , wherein the pores have a pore size that is less than about 1 μm. 
     
     
         39 . The valve of  claim 21 , wherein the pores have a pore size that is less than about 0.10 μm. 
     
     
         40 . The valve of  claim 21 , further comprising a support structure, the at least one leaflet being supported on the support structure and movable between open and closed positions. 
     
     
         41 . The valve of  claim 40 , wherein the support structure is selectively diametrically adjustable for endovascular delivery and deployment at a treatment site. 
     
     
         42 . The valve of  claim 21 , wherein the synthetic polymer membrane is expanded fluoropolymer membrane, and wherein the elastomeric or elastomeric material is a TFE/PMVE copolymer, and wherein the valve is operable to be a prosthetic heart valve. 
     
     
         43 . A valve, comprising:
 at least one leaflet operable to move between open and closed positions, each leaflet including a composite material comprising a synthetic polymer membrane having a plurality of pores and TFE/PMVE copolymer present in substantially all of the pores, the composite material comprising TFE/PMVE copolymer by weight in a range from about 10% to about 90%.