摘要:
An improved gasket particularly suitable for use in sensitive environments is disclosed. The preferred gasket of the present invention comprises at least one layer of a composite material of porous polytetrafluoroethylene (PTFE) polymer and resilient expandable microspheres. The composite material provides a number of significant advantages over existing PTFE and similar clean gaskets, including better seal under less compressive pressure, sufficient resilience to permit reuse, and retained porosity--allowing pressure equalization in the equipment to occur through the gasket itself.
摘要:
The present invention provides improved compositions of expanded polytetrafluoroethylene (PTFE) and similar polymers and methods for forming and using such compositions. In its preferred embodiment, the present invention employs a mixture of PTFE and expandable thermoplastic microspheres. Through application of an energy source to the mixture, a coherent three dimensional expansion of PTFE can be achieved. The expanded mixture has many of the same beneficial properties of mechanically expanded PTFE and numerous properties previously unavailable with expanded PTFE products.
摘要:
A fiber of expanded porous polytetrafluoroethylene in which an amount of a conductive particulate filler is incorporated imparting a measure of conductivity to the fiber is disclosed. The fiber may be twisted along its length. The fiber may be a continuous monofilament fiber, a tow, a staple, or a flock.
摘要:
A flexible patch electrode for use with living tissue, comprising, in sequential laminar form, a layer of electrically conductive porous polytetrafluoroethylene, a layer of polymeric adhesive, a layer of electrically conductive sheet material having lower resistivity than the layer of porous polytetrafluoroethylene, and an insulating layer. The layer of electrically conductive sheet material is of less length and width than the adjacent layers and is placed so that its edges are not exposed at the edges of the flexible patch electrode.
摘要:
A substrate comprising a microporous microstructure, an interlayer over at least a portion of the microstructure and a functional layer attached to the interlayer, the functional layer having functional sites with a density of at least 50 nanomoles/cm2.
摘要:
A thermally conductive interface is provided suitable for thermal conduction, especially between electronic components. The preferred thermally conductive interface comprises an open structure fluoropolymer material, such as expanded polytetrafluoroethylene, with uncoated thermally conductive particles attached to solid portions thereof. The interface has numerous benefits over previously available material, such as improved thermal conductivity, high conformability, better compressibility, inherent porosity so as to provide air relief, improved stress relief, and high material compliance and resistance to fatigue during thermal cycling.
摘要:
The present invention provides for a bone growth material for filling in defects or hollow portions of bones to be ingrown by and coalesce with bone tissues wherein the bone growth material is comprised of expanded PTFE and calcium phosphate.
摘要:
A method of using an improved catalytic filter material for removing contaminants such as NO.sub.x from a fluid stream. The filter employs composite fibers of expanded polytetrafluoroethylene (PTFE) filled with catalytic particles. The composite fibers are chopped into staple fibers and made into a felt material. Preferably, the felt material is then laminated on at least one side with a protective microporous membrane. The combined filter removes both macro-particles, such as dust, from the filter stream before the dust can clog active catalytic sites and effectively catalytically coverts undesirable contaminants in the fluid stream to acceptable end products.
摘要:
An improved low noise electrical signal transmission cable is disclosed. The cable employs an insulative layer of expanded polytetrafluoroethylene (PTFE) which is bonded in fixed relative position with a surrounding shield layer through use of an adhesive, such as fluorinated ethylenepropylene (FEP) or perfluoroalkoxy polymer (PFA). The bonding process reduces the separation of layers which can sometimes occur with expanded PTFE insulative cables and avoids the generation of unwanted triboelectric signals that can result from such separation.
摘要:
A filled PTFE film is prepared by compressing an expanded, porous PTFE film that contains filler material. The films have high strength with substantially few pinholes.