Abstract: A method of making a composite membrane with ion exchange properties includes, in an exemplary embodiment, forming a porous membrane from a first material, dissolving a coating material in a fluid at supercritical conditions, and exposing the porous membrane to the coating material dissolved in the supercritical fluid. The method also includes precipitating a uniform coating of the coating material onto an exterior surface of the porous membrane by changing the supercritical conditions of the fluid to a non-supercritical condition, and applying an ion exchange material to the coated porous membrane so that the ion exchange material is in intimate contact with substantially all of the coated surfaces of the porous membrane.

Abstract: A composite article, in an exemplary embodiment, includes a porous base membrane made from a first material having hydrophobic properties, and a coating layer formed on at least a portion of the porous membrane. The coating layer includes a crosslinked coating material, and has hydrophilic properties.

Abstract: A composite article, in an exemplary embodiment, includes a porous membrane formed from a first material, a coating formed from a second material applied to at least a portion of the porous membrane, and a third material covering at least a portion of the porous membrane. The third material is substantially incompatible with the first material. The second material of the coating is compatible with the first material and the third material. The coating is positioned between the first material and the third material The third material is connected to the first material by the coating on the porous membrane.

Abstract: An air permeable composite article that in one embodiment includes a porous base membrane that includes a plurality of nodes and fibrils defining a plurality of interconnecting pores extending through the porous base membrane with each node and fibril having a surface. The composite article also includes a precipitated coating material deposited on the surfaces of the plurality of nodes and fibrils. The coating material includes a copolymer formed from a fluorinated acrylate or methacrylate, an n-alkyl acrylate or methacrylate, and an isocyanate crosslinker. The precipitated coating material provides oil and contaminating agent resistance of at least a number six measured in accordance with AATCC 118 test method.

Abstract: The present invention is a method for modifying at least one property of a porous membrane. The method comprises the steps of providing a porous membrane. The method also includes exposing the membrane to a fluid at supercritical conditions. At least one property of the membrane is modified while the membrane is exposed to the fluid at supercritical conditions. The condition of the fluid is changed in such a manner that the porous membrane retains the modified property. The present invention is also sheet material that is water-resistant, moisture vapor transmissive and air permeable. The sheet material comprises a membrane having an open pore structure including surfaces defining a plurality of interconnecting pores extending through the membrane and between major sides of said membrane in which the pores have an average pore size. The membrane is made from a material tending to absorb oils and contaminating agents.

Abstract: The present invention is a method for modifying at least one property of a porous membrane. The method comprises the steps of providing a porous membrane. The method also includes exposing the membrane to a fluid at supercritical conditions. At least one property of the membrane is modified while the membrane is exposed to the fluid at supercritical conditions. The condition of the fluid is changed in such a manner that the porous membrane retains the modified property. The present invention is also sheet material that is water-resistant, moisture vapor transmissive and air permeable. The sheet material comprises a membrane having an open pore structure including surfaces defining a plurality of interconnecting pores extending through the membrane and between major sides of said membrane in which the pores have an average pore size. The membrane is made from a material tending to absorb oils and contaminating agents.