a porous fluoropolymer alloy material and method of fabrication is provided . the alloy material is fabricated by forming a compressed extrusion billet from two or more fluoropolymer resins capable of being stretched after extrusion and having different stretch characteristics . the fluoropolymer alloy billet is then extruded , stretched and sintered . the resulting material has a microstructure of large nodes interconnected by fibrils all oriented in the direction of stretch and has a higher tensile strength than produceable from previous porous fluoropolymer materials . also , the resulting material can be made at lower stretch rates and at higher stretch ratios than previously possible without degradation of the material &# 39 ; s strength . in one embodiment the resulting product is a self - supporting , tunable asymmetric porous fluoropolymer alloy material having a microstructure comprised of relatively small nodes , short fibrils and small pore size on one surface and relatively large nodes , long fibrils and large pore size on the opposite surface . the microstructure of the material gradually changes from the microstructure of the one surface to the microstructure of the opposite surface through the cross - section of the material &# 39 ; s thickness , and all of the fibrils throughout the material are oriented in the direction of stretch .