Abstract: Charged, high-strength, high-modulus, melt-processed microfibers, films having a charged, microfibrillated surface, and methods of making the same are described. Charged microfibrillated articles of the invention can be prepared by imparting fluid energy, typically in the form of high-pressure water jets, to a highly oriented, highly crystalline, melt processed film to liberate microfibers or microfibrous flakes therefrom. Microfibrillated articles of the invention find use as tape backings, in the preparation of woven or nonwoven articles, filters for particulate contaminants, such as face masks and water or air filters, fibrous mats, such as those used for removal of oil from water, wipes for dust or debris removal, and thermal and acoustical insulation.

Abstract: A method of making an electret that includes contacting a porous substrate that includes polymer with a composition that includes solvent capable of swelling the polymer, removing the solvent from the substrate, and contacting the substrate with water in a manner sufficient to impart an electret charge to the substrate.

Abstract: Charged, high-strength, high-modulus, melt-processed microfibers, films having a charged, microfibrillated surface, and methods of making the same are described. Charged microfibrillated articles of the invention can be prepared by imparting fluid energy, typically in the form of high-pressure waterjets, to a highly oriented, highly crystalline, melt processed film to liberate microfibers or microfibrous flakes therefrom. Microfibrillated articles of the invention find use as tape backings, in the preparation of woven or nonwoven articles, filters for particulate contaminants, such as face masks and water or air filters, fibrous mats, such as those used for removal of oil from water, wipes for dust or debris removal, and thermal and acoustical insulation.

Abstract: Charged, high-strength, high-modulus, melt-processed microfibers, films having a charged, microfibrillated surface, and methods of making the same are described. Charged microfibrillated articles of the invention can be prepared by imparting fluid energy, typically in the form of high-pressure water jets, to a highly oriented, highly crystalline, melt processed film to liberate microfibers or microfibrous flakes therefrom. Microfibrillated articles of the invention find use as tape backings, in the preparation of woven or nonwoven articles, filters for particulate contaminants, such as face masks and water or air filters, fibrous mats, such as those used for removal of oil from water, wipes for dust or debris removal, and thermal and acoustical insulation.

Abstract: A method of removing particulate solid or liquid aerosol from a gas, which method comprises the step of: passing a particulate solid or liquid aerosol containing gas through an electret filter that comprises a polymer and a performance enhancing additive, wherein the electret filter has a thermally stimulated discharge current (TSDC) spectrum exhibiting a peak having a width at half height of less than about 30° C., as measured by TSDC test procedure 3.

Abstract: Novel electret articles containing a polymer and a performance-enhancing additive can be identified by their thermally stimulated conductivity characteristics or their filtration properties. Electret articles such as nonwoven filter webs and respirators exhibit superior oily mist loading performance, low penetration and a small pressure drop.

Abstract: The thermally stimulated discharge current of an electret article can be used to identify electret articles that exhibit superior filtration properties. Electret filters that exhibit superior properties not achieved in similarly constructed filters contain fibers that are made from a blend of a polymer and a performance-enhancing additive. The electret filters exhibit an initial detectable DOP penetration of less than 5% and an average Min@Chl of greater than 200 mg DOP as measured by DOP Filter Web Loading Test Procedure 1. These new electrets are particularly useful in a respirator.

Abstract: An electret article can be made by quenching a molten blend containing a polymer and a performance-enhancing additive. The resulting low crystallinity material can be annealed and charged to produce a material for making electret filters having superior oily mist loading performance properties.