Porous fluoropolymer alloy and process of manufacture

An asymmetric porous fluoropolymer alloy material, comprising:

• a first layer of a fluoropolymer resin capable of being highly stretched after extrusion;
• a second layer of at least one second fluoropolymer resin capable of being stretched to a lesser degree than said resin of said first layer;
• wherein said first and second layers are mechanically bonded to form an alloy;
• and
• wherein the material has a microstructure comprising nodes interconnected by fibrils, and wherein the size and length of the fibrils change through the cross-section of the material from one surface of the material to the opposite surface of the material.

A porous fluoropolymer alloy material having a microstructure comprising nodes interconnected by fibrils, manufactured from a process comprising the steps of:

• forming an extrusion billet comprising a first fluoropolymer resin capable of being highly stretched after extrusion and at least one second fluoropolymer resin capable of being stretched to a lesser degree than said first fluoropolymer resin;
• extruding said extrusion billet to form an extrudate;
• stretching said extrudate at a temperature below the crystalline melting point of said extrudate;
• and
• sintering said stretched extrudate by heating said stretched extrudate to a temperature above the crystalline melting point of said extrudate.

An asymmetric porous fluoropolymer alloy material having a microstructure comprising nodes interconnected by fibrils and wherein the size and length of the fibrils change through the cross-section of the material from one surface of the material to the opposite surface of the material, manufactured from a process comprising the steps of:

• forming an extrusion billet comprising a first layer of a fluoropolymer resin capable of being highly stretched after extrusion and a second layer of at least one second fluoropolymer resin capable of being stretched to a lesser degree than said resin of said first layer;
• extruding said extrusion billet to form an extrudate;
• stretching said extrudate at a temperature below the crystalline melting point of said extrudate;
• and
• sintering said extrudate by heating said at a temperature above the crystalline melting point of said extrudate.

An asymmetric porous fluoropolymer alloy material having a microstructure comprising nodes interconnected by fibrils and wherein the size and length of the fibrils change through the cross-section of the material from one surface of the material to the opposite surface of the material, manufactured from a process comprising the steps of:

• forming an extrusion billet comprising a first layer of a fluoropolymer resin capable of being highly stretched after extrusion, a second layer of a fluoropolymer resin capable of being stretched to a lesser degree than said resin of said first layer, and a third layer, disposed between said first and second layers, of a mixture of said resins of said first and second layers;
• extruding said extrusion billet to form an extrudate;
• stretching said extrudate at a temperature below the crystalline melting point of said extrudate;
• and
• sintering said stretched extrudate by heating said stretched extrudate to a temperature above the crystalline melting point of said extrudate.

A method of manufacturing a porous fluoropolymer alloy material having a microstructure comprising nodes interconnected by fibrils, comprising the steps of:

• forming an extrusion billet comprising a first fluoropolymer resin capable of being highly stretched after extrusion and at least one second fluoropolymer resin capable of being stretched to a lesser degree than said first fluorocarbon resin;
• extruding said extrusion billet to form an extrudate;
• stretching said extrudate at a temperature below the crystalline melting point of said extrudate;
• and
• sintering said stretched extrudate by heating said stretched extrudate to a temperature above the crystalline melting point of said extrudate.

A method of manufacturing an asymmetric porous fluoropolymer alloy material having a microstructure comprising nodes interconnected by fibrils and wherein the size and length of the fibrils change through the cross-section of the material from one surface of the material to the opposite surface of the material, comprising the steps of:

• forming an extrusion billet comprising a first layer of a fluoropolymer resin capable of being highly stretched after extrusion and a second layer of at least one second fluoropolymer resin capable of being stretched to a lesser degree than said resin of said first layer;
• extruding said extrusion billet to form an extrudate;
• stretching said extrudate at a temperature below the crystalline melting point of said extrudate;
• and
• sintering said stretched extrudate by heating said stretched extrudate to a temperature above the crystalline melting point of said extrudate.

A method of manufacturing an asymmetric porous fluoropolymer alloy material having a microstructure comprising nodes interconnected by fibrils and wherein the size and length of the fibrils change through the cross-section of the material from one surface of the material to the opposite surface of the material, comprising the steps of:

• forming an extrusion billet comprising a first layer of a fluoropolymer resin capable of being highly stretched after extrusion, a second layer of a fluoropolymer resin capable of being stretched to a lesser degree than said resin of said first layer, and a third layer, disposed between the said first and second layers, of a mixture of said resins of said first and second layers;
• extruding said extrusion billet to form an extrudate;
• stretching said extrudate at a temperature below the crystalline melting point of said extrudate;
• and
• sintering said stretched extrudate by heating said stretched extrudate to a temperature above the crystalline melting point of said extrudate.