Abstract: A filtration structure comprising a thermally bonded, wet laid, fibrous web and support is provided. The web is formed from bicomponent fiber comprising a structure-forming component and a heat-bondable component. Also provided is a filtration method using the filtration structure. Beneficially, the filtration structure may include microfiber.

Abstract: A method for separating co-mingled polymeric materials, in particular polyethylene terephthalate (PET) and polyvinyl chloride (PVC) is described. The process involves selectively dissolving a supercritical fluid into one of the materials at the appropriate temperature and pressure. Upon rapid reduction of the system pressure, the selected material foams providing a change in density. Under ambient conditions, the polymeric materials having a large density difference can be separated by means of aqueous separation and flotation. The preferred supercritical fluid for the process is carbon dioxide, and PVC is the material into which the supercritical fluid is preferentially dissolved.

Abstract: A high efficiency air filtration media comprises: about 5 to about 20% by weight of fibrids; about 5 to about 20% by weight of a binder; and about 60 to about 90% by weight of staple fiber. The media has a pressure drop of air across a face of the media of less than or equal to 0.4 inches of water. The media, also, has a sodium chloride particulate test for respirator filter percent efficiency of greater than or equal to 60%.

Abstract: A solution polybenzimidazole which is resistant to phase separation contains: a polybenzimidazole; a solvent capable of dissolving the polybenzimidazole; and a minor amount of ammonium acetate.