Abstract: A highly conductive polyacetylene film is obtained by orienting a catalyst-containing polyacetylene film or an essentially catalyst-free polyacetylene film which has been swelled in a solvent after the catalyst has been washed out, the polyacetylene being essentially free of sp.sup.3 -hybridized carbon atoms.

Abstract: A method of producing self-supporting ceramic bodies having a modified metal-containing component includes first providing a self-supporting ceramic body comprising (i) a polycrystalline oxidation reaction product formed upon oxidation of a molten parent metal precursor with an oxidant, and (ii) an interconnected metal-containing component at least partially accessible from one or more surfaces of said ceramic body. The surface or surfaces of the ceramic body is contacted with a quantity of foreign metal different from said interconnected metal-containing component at a temperature and for a time sufficient to allow for interdiffusion, whereby at least a portion of said metal-containing component is displaced by said foreign metal. The resulting ceramic body, having an altered metal-containing component, exhibits modified or improved properties.

Abstract: A mold (1) for cast-molding a slip is provided, which comprises a divsible casting mold including a plurality of mold portions to form a mold cavity (4) when mated together; each mold portion including an air-tight housing (2), an intermediate layer (5) of coarsely porous structure adjacent to the air-tight housing (2), and a solid synthetic resin filter layer (3) of fine open-cell structure; a slip supply duct (8) being connected with said mold cavity (4) and communicated with the outside of the air-tight housing (2); a fluid-flowing duct (9) being connected with said coarse intermediate layer (5) and communicated with the outside of the air-tight housing (2); said filter layer (3) being permeably joined to the coarse intermediate layer (5), and having substantially precise shape and dimension of substantially uniform fine open-cell structure.

Abstract: For producing solution/diffusion membranes, homogeneous dense films prepared by melt extrusion or casting from synthetic polymers, having a melting temperature above 140.degree. C., a glass transition temperature above 0.degree. C. and long time stability against boiling ethanol are irradiated with accelerated electrons and submitted to a subsequent radical graft copolymerization. After graft polymerzation, the functional groups are converted into the dissociated salts.

Abstract: Filament wound or dry lay-ups of structural shapes are impregnated with a binder of thermoplastic resin. Impregnation is achieve by adding a polymer solution to a centrifuge containing reinforcing material. The centrifuge is spun at high rotational speed. Solution is metered into the centrifuge and contacts the inner surface of the reinforicng material. A preheated carrier gas flow is circulated in the centrifuge using baffles, then released to a solvent recovery system. Alternatively, vacuum drying to recover solvent can be used.

Abstract: A composite self-supporting flexible agglomerated macrostructure is described which includes (1) a matrix of unfibrillated polytetrafluoroethylene resin and addition curable silicone and (2) particulate material including hydroxyapatite and/or tricalcium phosphate uniformly distributed throughout said matrix, the macrostructure being uniformly permeated by a network of open pores formed in the process of manufacture by intimately blending particulate sodium chloride and subsequently leaching the sodium chloride particles.

Abstract: A method for making a component for a semi-conductor diffusion furnace by blending two types of silicon carbide powders, that is, 10 parts by weight of intermediate silicon carbide having an average particle size of 10-30 microns and 10-25 parts by weight of coarse silicon carbide having an average particle size of 80-200 microns, thereby to make a mixture, admixing an organic binder with the mixture, thereafter granulating the mixture thereby to produce pellets, preforming the pellets by a rubber press thereby to produce a formed body, presintering the formed body thereby to produce a presintered body, and impregnating the presintered body with silicon and simultaneously sintering it.

Abstract: The present invention relates to a process to remove residue from partially hydrogenated nitrile rubber. The process is undertaken by mixing and kneading the rubber in the presence of an extractant fluid. The extractant fluid is a solvent for the residue but is not a solvent for the rubber. At the conclusion of the process, the rubber is separated from the residue-containing extractant fluid.

Abstract: The method of preparing dried asymmetric cellulose acetate blend membranes through the use of at least one drying agent which is a hydrophobic organic compound, such as polysiloxanes, hydrocarbons, ethers, ketones, chlorohydrocarbons or nitrohydrocarbons. The membranes are dried from their aqueous state by direct evaporation of water. The resulting air dried membranes are suitable for the desalination of water by reverse osmosis, non-aqueous liquid separation, ultrafiltration, pervaporation, and for the separation of various gaseous mixtures into their constituent parts.

Abstract: The present invention provides a process for producing a wound dressing delivery system. The wound dressing delivery system is formed by extruding first and second thermoplastic resins onto the surface of a carrier sheet to form first and second thermoplastic films; the first thermoplastic film functions as a temporary support for the second thermoplastic film and the second thermoplastic film functions as a wound dressing and has a moisture vapor transmission rate of greater than 300 grams/square meter/24 hours (ASTM E-96:37.8.degree. C./90% R.H.). The first thermpolastic resin is extruded onto the surface of the carrier sheet and the second thermoplastic resin is extruded onto the surface of the first thermoplastic film such that the first thermoplastic film is interposed between the carrier sheet and the second thermoplastic film.

Abstract: A method of producing a plastic sheet with a porous surface layer suitable for use as, for example, a recording medium on which characters and images are printed by ink jet or thermal-transfer printing method. The method comprises preparing a solution by dissolving two or more kinds of plastics having low levels of miscibility to each other in a solvent, applying said solution to a substrate, passing said substrate with said solution applied thereto through a liquid which dissolves said solvent but does not dissolve said plastics thereby solidifying said plastics, and drying said substrate with the solidified plastic layer. Preferably, two or more kinds of plastics having low levels of miscibility to each other include mainly a material A which is vinyl chloride or its compolymer and a material B which is acrylonitrile or its copolymer.

Abstract: The present invention provides a fiberglass composite which possesses outstanding armor properties. This ballistic resistant composite material employs a high strength magnesia aluminosilicate glass fabric and a prescribed phenol formaldehyde condensation product as the matrix resin. The composite is produced from a prepreg by molding under controlled conditions and the prepreg material is formed with a controlled heating cycle.

Abstract: A method of recovering a solid flowable polymer medium that is capable of being used as a pressurizing medium for high temperature molding from contaminants. A polymer mixture containing contaminants that was a solid flowable polymer medium prior to exposure to temperatures in excess of about 316.degree. C. during its use as a pressurizing medium is disposed in a solution. The solution has a specific gravity greater than the solid flowable polymer medium. The solid flowable polymer medium is separated from the surface of the solution and contamination settles to the bottom.

Abstract: A method of producing a high density and high strength silicon carbide member for a heat treatment furnace to be used in the manufacture of a semiconductor device. In this method, SiC powder, carbon powder, deflocculating agent and water are mixed to form a slip. Then the slip is formed into a desired shape, cured under a nonoxidizing atmosphere, and removed of any impurity contained in the shaped body. Finally, the shaped body is immersed in a molten silicon to convert the carbon in the shaped body into silicon carbide.

Abstract: There is provided a method of removing binding material from a shaped preform (green body) in the preparation procedure for the manufacture of ceramics from particulate materials by a new method comprising exposing the green body to a liquidified fluid to dissolve the binder materials in a liquidified fluid without deformation of the shape of the article. In the method, the binder materials can be removed without swelling of the article because the green body is not exposed to a rapid temperature increase and the binder does not volatilize in the body. Further the binder material can be removed in a shorter period of time from the entire body.

Abstract: A method for producing an alumina of high purity, which comprises forming an oxidation reaction product of an aluminum parent metal and an oxygen-containing vapor-phase oxidant, comminuting the resulting ceramic body, and leaching any non-alumina materials therefrom, and recovering said substantially pure alumina material.

Abstract: A process for reducing edge curl in green sheets in which the sheets are first placed in a chamber at about 95% relative humidity for a period of about 2 weeks at room temperature. In this part of the process, the sheets absorb water which causes the internal stresses in the green sheet to relax. Thereafter, the sheets are dried by placing them in a chamber at about 35% relative humidity for a period of about 1 week at room temperature. In this period, the absorbed water evaporates and the green sheets become firm with less edge curl than they exhibited prior to the treatment.

Abstract: A method of binder removal from a green body before sintering or the like wherein the binder is constituted of a polymeric material or mixture which is degradable by thermo-oxidation and the green body is initially heated to a temperature where the binder reaches an energy level above the activation energy of the binder, as a result of which exothermic degradation reactions are initiated at the binder-atmosphere interface. The rate of the exothermic reaction is controlled by the rate of supply of thermal energy and oxygen to the reaction site as well as the rate of evacuation of the heat of reaction generated during the thermal oxidation. Substantially all of the binder is thus removed from the green body which can then be sintered in accordance with the practices of the prior art.

Abstract: A reversed phase analogue of at least part of a first membrane having substantially interconnected pores is formed by first filling at least some of the pores of the first membrane with a fluid that will form the analogue membrane and then forming the analogue membrane in the pores of the first membrane. The first membrane is then removed from the analogue membrane. The structure of the analogue membrane is of different morphology from that of the first membrane and the reversed phase nature arises because it is the pores of the first membrane which lead to the formation of the walls of the reversed phase membrane and it is the walls of the pores of the first membrane which lead to the formation of the pores of the reverse phase membrane.

Abstract: A carbonizable body is formed by infusing a plurality of preoxidized, preferably stabilized by known processing to have about 9 to 14 weight percent oxygen, polyacrylonitrile fibers in a polar liquid plasticizer, preferably water, capable of extracting a tarry leachate from the fibers. The infusion of the fibers in the plasticizer is continued for a sufficient time for a substantial amount of leachate to form on the surface of the fibers, and are then consolidated or diffusion-bonded to one another or other fibers, as by orienting the treated fibers in a mold and subjecting them to isostatic pressing at relatively low temperatures and pressure. Further processing of the consolidated fibers with appropriate heat treatment in an inert atmosphere will produce a carbonized bulk product with higher values of Young's modulus for the carbonized material than have been previously achieved at such carbonization temperatures.

Abstract: A carbonizable body is formed by infusing a plurality of preoxidized, preferably stabilized by known processing to have about 17 to 30 weight percent oxygen, fibers prepared from pitch, in a non-polar liquid plasticizer, typically quinoline, capable of extracting a tarry leachate from the fibers. The infusion of the fibers in the plasticizer is continued for a sufficient time for a substantial amount of leachate to form on the surface of the fibers. The treated fibers are then consolidated or diffusion-bonded to one another or other fibers, as by orienting the treated fibers in a mold and subjecting them to isostatic pressing at relatively low temperatures and pressure. Further processing of the consolidated fibers with appropriate heat treatment in an inert atmosphere will produce a carbonized bulk product with higher values of Young's modulus for the carbonized material than have been previously achieved at such carbonization temperatures.

Abstract: A method for preparing an alcohol insoluble polymide membrane. An appropriate membrane-forming casting liquid containing the required polyamide is evaporated under conditions of high total humidity and an air flow of less than 305 m/min. (1000 ft/min) in order to form the membrane. Membranes of a single polyamide, e.g. Nylon 6,6 can be formed by the method.

Abstract: A method of treating PET preforms and bottles consists of subjecting the preforms or the bottles to a carbon dioxide atmosphere at a higher temperature than the critical temperature of carbon dioxide, a higher pressure than ambient pressure, and for a set time period. The treatment reduces the acetaldehyde concentration in the head of the treated bottles or in the bottles obtained from the treated preforms by stretch-blowing, and also reduces the permeability of gases through the bottle walls.

Abstract: A process for preparing improved pellets of a hydrolyzed ethylene-vinyl acetate copolymer which comprises extruding a methanol or a water-methanol solution including a hydrolyzed ethylene-vinyl acetate copolymer and a lubricant into a coagulating liquid in the form of a strand and cutting the strand into pellets. According to the process of the present invention, the molding processability can be improved without damaging the properties of the molded articles.

Abstract: A method of manufacturing heating furnace parts having high purity which comprises the steps of molding a raw powder mainly consisting of silicon carbide powder into a prescribed form, and subjecting the molded product to a purification treatment at a temperature ranging between 1,500.degree. and 2,100.degree. C. in an atmosphere containing a gas selected from the group consisting of halogen gas and hydrogen halide gas, and an inert gas applied as a carrier gas.

Abstract: A method is disclosed for providing a clean, highly conductive mating surface in a composite panel which includes an embedded aluminum wire mesh to achieve lightning and electromagnetic interference shielding. The method includes the steps of laying a nonporous tape in a mold corresponding with the area requiring a highly conductive mating surface, laying one or more plies of aluminum mesh thereover to provide a conductive path, and then laying a nonporous barrier tape ply above the mating surface, sandwiching the metal mesh therebetween, with structural plies laid thereover. During curing, the tapes prevent direct resin inclusion into the metal mesh. After curing, the nonporous tape is removed to expose the clean, highly conductive mating surface. Utilizing the above-described method substantially increases the ability to provide a clean conductive mating surface without utilizing extensive equipment or processing steps, providing enhanced EMI shielding in composite structures.

Abstract: A method for producing nonspherical particles including those of prolate spheroidal, oblate spheroidal, and ellipsoidal shape is described. A microparticulate latex can be produced wherein the microparticles in the latex are substantially identical in all dimensions. The overall shape, volume, and aspect ratio or aspect ratios of the particles can be systematically controlled. Non-spherical particles ranging in sizes from about 0.01 microns to about 100 microns can be produced from a variety of polymeric materials. Such particles can be used as model particles for a variety of scientific studies, calibration standards for electron microscopes, and in a variety of optical, thermal, electrical, and biomedical applications.

Abstract: Permselective membranes are disclosed which comprise a layer comprising polystyrene, at least a portion of which is sulfonated, and between about 10 wt. % and about 35 wt. % monovinyl arene-hydrogentated diene block copolymer, at least a portion of which is sulfonated. The membranes exhibit a resistance of less than about 8 .OMEGA.-cm.sup.2 in 7 wt. % Na.sub.2 SO.sub.4 and an ion exchange capacity of between about 1.0 meq/g and about 1.6 meq/g. Monopolar and bipolar membranes comprising the layer are disclosed. A preferred process for forming the membranes comprises the steps of sulfonating polystryene and monovinyl arene-hydrogenated diene block copolymer, forming a mixture of the materials in a solvent, forming a layer of the mixture and drying the layer to form at least a portion of the membrane.

Abstract: A method for eliminating a dispersion medium from a molded product obtained by plasticizing-molding or casting-molding one or more of metallic and ceramic powders, wherein the elimination process is carried out in a supercritical liquid carbon dioxide atmosphere without heating to higher temperatures.

Abstract: The invention relates to a method of removing binder materials from a shaped preform (green body) in the preparation procedure for the manufacture of ceramics from particulate materials. The new method comprises exposing the green body to a supercritical fluid to dissolve the binder materials in the supercritical fluid without deforming the shape of the article. In the method, the binder materials can be removed without swelling of the article because the green body is not exposed to a rapid temperature increase and the binder does not volatilize in the body. In addition, the binder material can be removed in a drastically shorter period of time from the entire body.

Abstract: Pharmaceutical compositions are provided which contain hollow fine tube drug delivery systems. The compositions comprise a pharmaceutically suitable carrier, preferably in the form of a capsule, tablet, suspension, or suppository, and at least one drug delivery system which consists essentially of (1) a polymeric tube having a membrane outer sheath and a hollow core, and (2) at least one drug compound contained within the core, said system contained in the composition in an amount sufficient to deliver a therapeutic amount of the drug contained therein at a predetermined rate over a predetermined period of time. By varying the polymer, the permeability of the outer sheath, the drug, the drug concentration in the hollow core of the tube, the tube diameter, the tube length, the tube core diameter, and the sealing of the tube ends, a wide variety of drug therapeutic amounts, rates and dosing times can be achieved.

Abstract: A treatment process for treating an interfacially polymerized polyaramide on a microporous support reverse osmosis membrane. The treatment involves immersing the membrane in an aqueous solution containing 5 to 25 weight percent of an alcohol having 1-5 carbon atoms for 15 minutes to two hours at a pressure of 50 to 100 psi. Optionally, the membrane can be treated with a surfactant.

Abstract: A process for dewaxing a ceramic molded body is disclosed, the process includes heating an injection molded body made from ceramic material and a wax-series binder, said heating occurring upon a porous ceramic body.

Abstract: A method for fabricating large, greater than one centimeter cross section, high density silicon nitride by injection molding process has been developed. The method requires use of a controlled starting powder, a novel binder removal process, a prefiring step followed by isopressing and conventional sintering.

Abstract: A method for fabricating injection molded ceramic shapes suitable for densification by sintering or hot isostatic pressing has been developed. The method is applicable to ceramic articles of large, complex cross sections, greater than one centimeter, which are generally prone to external cracking during binder removal. The method requires use of a controlled starting powder, and a novel binder removal process to obtain an externally crack-free article.

Abstract: Polyimide film prepared from a precursor solutions of polyamic acid in a solvent can be dried during or following the thermal or chemical conversion step, which produces a polyimide, by adding to the solution a small amount of an alkyl ester of phthalic, terephthalic, or isophthalic acid, casting the solution on a flat surface and heating the solution on the flat surface at about 100.degree.-200.degree. C.; then, removing the resulting partially converted film from the flat surface and heating it, under restraint, to about 200.degree.-375.degree. C., to bring about complete conversion and remove virtually all of the solvent. Polyimide films are useful in various applications where high temperature resistance is required, including composites for aerospace applications and for circuit boards for electronic equipment.

Abstract: A method for the manufacture of high-strength, high-density carbon materials is disclosed. The method comprises the steps of pulverizing a carbonaceous raw material having a carbon content of at least 92% by weight, a volatile content of 7-20% by weight up to 900.degree. C., and linear shrinkage as a molded body of at most 6% during heating up to 500.degree. C. to an average particle diameter of greater than 10 .mu.m and at most 40 .mu.m, followed by molding and baking. An organic fiber after baking in an inert atmosphere at a temperature of at least 400.degree. C. may be mixed with the pulverized carbonaceous raw material.

Abstract: A gas diffusion composite electrode is disclosed which is suitable for use in combination with an electrically conductive current collector. The electrode comprises an electrochemically active, porous and heterogeneous layer containing (1) an interconnected, hydrophilic island material comprising a blend of a major amount of an electrically conductive, particulate material, such as carbon black, in combination with an electrochemically active catalyst, and a minor amount of a hydrophobic polymer in combination with (2) a hydrophobic matrix material consisting essentially of a hydrophobic polymer rendered substantially porous by removal of a pore-forming ingredient. Methods of preparing the heterogeneous layer and the composite electrode are also disclosed.

Abstract: The present invention contemplates a method of manufacturing a laminated sheet having a non-skid surface. In a preferred embodiment a method of manufacturing a decorated unitary laminated tray having a thermoplastic non-skid layer is disclosed.

Abstract: The isolation of polyarylene sulphides by freeing polyarylene sulphides of the type obtained in customary production processes from adherent water and any other volatile constituents by treating the polyarylene sulphides in screw machines and optionally melting them either simultaneously or subsequently.

Abstract: A thin-walled guiding catheter of the type having a distal end adapted to be formed into curved configurations and passed through branching blood vessels and the like is prepared with a three-layered tubular body portion having a lubricious inner sheath defining a lubricious guiding lumen, a rigid intermediate sheath, and a flexible outer sheath, which may be radiopaque. The distal tip portion thereof has a similar construction, but from which the rigid intermediate sheath is omitted. The guiding catheter exhibits excellent torque response and control while being especially thin-walled, thereby permitting minimization of the outer diameter size while permitting passage of an intravascular catheter and the like through its lumen.

Abstract: A method of improving the quality of hot pressed Si.sub.3 N.sub.4 bodies is disclosed. Unpurified silicon powder and admixed oxygen carrying agents are compacted to form a preform. The preform is nitrided, facilitated by the presence of certain impurities, to agglomerate the mixture to an increased density no greater than 2.7 gm/cm.sup.3. The nitrided preform is immersed in one or more stages in one or more leaching solutions of effective concentration to remove the selected impurities. The treated preform is then hot pressed to full density accompanied by a substantial reduction or absence of undesirable impurities such as iron silicide, which can conventionally form during hot pressing.

Abstract: A method of manufacturing extremely high purity parts for use to the heating furnace comprising adding a sintering assistant of 0.5-2.0 weight % and a binder, to SiC powder which has an average particle diameter of 2 .mu.m or less, and molding it to a predetermined form; applying the purification treatment to this molded body by placing it in the 800.degree.-1,300.degree. C. atmosphere of a gas which is selected from a group consisting of halogen gas and hydrogen halide; degassing the purified molded body in vacuum under a temperature higher than that employed at the purification treatment; sintering the degassed molded body, and coating an SiC film on at least part of the sintered body according to the chemical vapor deposition.

Abstract: A method for producing a fabric item comprising the steps of producing a perforated substrate in the shape of the desired fabric item, supplying fibers to the perforated substrate, causing the fibers to engage the perforations in the substrate, and retaining the fibers in the perforations.

Abstract: Polyester fibers containing one or more oxalate complexes of the general formulaMe.sub.n [Z(C.sub.2 O.sub.4).sub.m ]are drawn and subjected to a hydrosetting process at temperatures of 90.degree. to 170.degree. C. in the presence of liquid water, the water containing one or more of the following surfactants: salts of partial esters of phosphoric aid, sulfosuccinic aid esters, phosphonic acid esters as well as ethoxylated silicon compounds, ethoxylated fatty alcohols, polyglycol esters of fatty acids as well as various imidazole salts of partially or completely hydrogenated imidazoles. In this way the hydrosetting process is accelerated and a more stable pore structure is obtained. Water absorption and retention are also increased.

Abstract: A process of making a wound dressing is suggested, in which a technical conventional viscose solution is mixed with a polysaccharide derivative; the mixture is treated at increased temperatures such that it is thermally coagulated; the coagulate is wetted with a polyalkylene glycol and dried, whereby a particulate structure of the wound dressing is produced.

Abstract: A method for manufacturing a resin-sealed semiconductor device wherein after a semiconductor pellet is sealed to a leadframe with a resin, outer leads projected from the leadframe and adhered with burrs are collapsed by their upper or upper and lower corners and then the burrs are removed by blasting.

Abstract: The present invention concerns improving the properties of cellulose carbamate fibres. The wet strength properties in particular can be improved by treating the fibres with alkalis or organic bases, aiming to reduce the number of carbamate groups. The procedure may also be applied in the manufacturing of regenerated cellulose fibres.

Abstract: Hot pressed refractory boride shapes are treated with molten alkali metal hydroxide such as by immersion in a bath of the molten hydroxide. The treatment cleans and removes residual carbon from the surface layer of the shapes.

Abstract: A process for making an encapsulated metal oxide varistor package comprises pressing the varistor powder mixture into a disc, sintering the pressed disc, followed by slow cooling to room temperature.The sintered disc is acid etched and a fritted-silver electrode applied on each side of the disc or in the alternative an aluminum coating is arc sprayed on each side of the disk followed by an arc sprayed copper coating on top of the aluminum coating. The fritted-silver electrode coating is heated to 660.degree. C. and slow cooled to room temperature. Sn-coated copper leads are soldered on the electroded disc of either electrode process and the assembly is encapsulated in resilient epoxy resin to form the encapsulated metal oxide varistor package.