The present invention relates to a polytetrafluoroethylene (PTFE) tube, and more particularly to a PTFE tube for a flexible hose. In particular the invention relates to a PTFE tube having a smooth bore for use in the production of a lined hose assembly farther comprising hose braids, external hose protection and end fittings. The PTFE tube comprises external roots and peaks, which tube is obtainable from a non-convoluted tube having an original wall thickness W.sub.0 and an internal diameter ID ...

A PTFE seal and method of fabrication therefor includes preparing a mixture of PTFE resin powder and a susceptor material which is then compacted and sintered by exciting the susceptor material with microwave energy. Preferably, the compaction and sintering of the mixture is carried out in a continuous process and a vacuum is drawn on the mixture in the heating zone to extract any air from the mixture. The sintered mixture is advanced, preferably continuously, to a cutting zone where PTFE wafers...

The fibrillated surface layer of an unsintered extruded mass of a polytetrafluoroethylene is broken by mechanical or electrical force to facilitate evaporation of the lubricant whereby a molded article which is free from defects such as cracks and blisters is obtained upon sintering.

An implantable microporous ePTFE tubular vascular graft exhibits long term patency, superior radial tensile strength and suture hole elongation resistance. The graft includes a first ePTFE tube and a second ePTFE tube circumferentially disposed over the first tube. The first ePTFE tube exhibits a porosity sufficient to promote cell endothelization tissue ingrowth and healing. The second ePTFE tube exhibits enhanced radial strength in excess of the radial tensile strength of the first tube.

Composition of nylon-6 and 5-25% fine particle size, waxy PTFE/0.01-10% nucleating agent for alpha crystallization of the nylon-6 ingredient. The composition is useful as a sleeve bearing for steel cable by virtue of its low friction and high wear resistance against such cable and the ease of extruding it from the melt to produce a flexible tube.

Non-sintered PTFE-bound electrodes for alkaline storage batteries are made by coagulating polytetrafluoroethylene (i.e. PTFE) particles from an aqueous dispersion thereof to form a gelatinous coagulum, mechanically dispersing the coagulum in water such that the coagulum is subdivided into small, sticky clots of PTFE particles which are suspended in the water, mixing the suspension with comminuted electrochemically active material to form a slurry of active material and active-material-coated clo...

A novel polytetrafluoroethylene (PTFE) material includes a plurality of aggregates connected together by a plurality of relatively long fibrils. Each of the aggregates are formed of PTFE nodes that are connected together by relatively short fibrils. Preferably, the long fibrils have lengths of 500 to 1000 microns and the short fibrils have a lengths of 10 to 30 microns. The aggregates have densities of less than 2.0 grams per cubic centimeter which is lower than the densities of the solid PTFE n...

A dual porosity PTFE tube including an inner surface of expanded PTFE material having a first porosity and an outer surface of expanded PTFE material having a porosity different from that of the inner surface. The preferred method includes the step of forming inner and outer preformed tubular billets of PTFE resin particles mixed with a lubricant; the outer billet is adapted to closely fit around and concentric to the inner billet. Porosity of the inner and outer surfaces is varied by changing, ...

A liquid lubricant or spray-on coating consisting essentially of polytetrafluoroethylene particles which are sintered and ground and then physically dispersed in a tricresyl phosphate carrier medium. The particles are pre-wet with aliphatic naphtha and are coated with 10 W. to 70 W. oil having a lower miscibility in tricresyl phosphate and a lower specific gravity than tricresyl phosphate. The diameter of particles is in the range of about 0.5 microns to about 20 microns. The stability of the di...

A composition is disclosed containing particulate polytetrafluoroethylene in amounts from 15 percent by weight to 80 percent by weight incorporated in an elastomer with an amount of molybdenum disulfide effective to permit its manufacture and in some cases lend its properties, and methods for preparing such compositions and for using molybdenum disulfide, and fibrillated particulate polytetrafluoroethylene to improve compositions and products are also disclosed.