Abstract: This invention provides a waterproof and breathable elastomeric polytetrafluoroethylene layered article for use in, for example, material for protective articles. The waterproof and breathable polytetrafluoroethylene layered article can for example, exhibit elastomeric properties of stretch to break of 275% in the machine direction, and 145% in the transverse direction and a total stretch recovery of at least 39% after being stretched to 75% extension for 100 cycles. This invention further provides a waterproof and breathable elastomeric polytetrafluoroethylene layered article bonded to a stretch fabric. The waterproof and breathable elastomeric polytetrafluoroethylene layered article bonded to a stretch fabric is thus durable and possesses a moisture vapor transmission rate exceeding 1000 gms/m.sup.2 day, and preferably above about 2000 gms/m.sup.2 day.

Abstract: Articles of manufacture having good green strength and low modulii of elasticity, and comprising a matrix of fibrillated polytetrafluoroethylene interconnecting and entrapping a high volume, at least about 85%, of a particulate and preferably a sinterable material selected from the group consisting of metals, intermetallic compounds, ceramics, salts, plastics, and combinations thereof. Said articles are formed by mechanically working a substantially dry mixture of a fibrillable polytetrafluoroethylene polymer and a high volume, at least about 85%, of the particulate material. Metal, ceramic and plastic articles prepared by heat treating, such as sintering, the articles of manufacture are also disclosed.The heat treated products are useful, inter alia, as structural elements and electronic components.

Abstract: Disclosed are gasket and seal materials comprising particulate material interconnected and entrapped by fibrillated polytetrafluoroethylene and methods for manufacturing and using them.

Abstract: Described are fluid processing devices primarily intended for filtration but which devices may also be used for dispensing or sparging liquids and gases into a body of fluid medium. According to the method of using the disclosed devices, fluid medium to be filtered is caused to flow over the active filtering surfaces of a filter medium, such as by rotating the filter element in the fluid medium, while the fluid medium is simultaneously caused to pass through the filter element. At predetermined intervals the fluid medium flow through the filter is reversed or backpulsed.Also disclosed are porous elements of laminated structure in propeller or disc configurations which may be coated with microporous active surfaces to permit filtration of extremely small sized particles from a fluid medium or dispensing of extremely small sized bubbles of gas or droplets of liquid into a body of fluid medium.

Abstract: A sintered filter element for mechanically separating suspended matter from a liquid or gaseous fluid medium to clarify same, comprising at least two laminated, porous, plate-like filter structures having relatively large planar front and rear surfaces joined by relatively small edge surfaces arranged substantially parallel to each other and spaced up to about five, preferably less than one, inches apart. Each filter structure comprises at least two contacting and adhered, substantially coextensive porous layers whose pores are in open communication over substantially all of the interface between their contiguous surfaces so as to permit flow of the fluid medium from one layer to the other. One of the layers is a retention layer for the suspended matter having a pore size sufficiently small substantially to prevent passage of the suspended matter to be removed from the fluid medium and the other of said layers is a supporting layer having a pore size larger than the pore size of the retention layer.