Abstract: A method for the heating of a fluid stream flowing in the pores of a body of specially prepared porous reticulated vitreous carbon which does not crack or substantially change in electrical resistance with time when heated to elevated temperature in air is described. The body is composed of electrically conductive rigid, interconnected and multidirectional continuous strands of vitreous carbon forming a rigid porous, three dimensional skeletal structure. The body as an electrical resistance element has current conductive paths between at least two regions; is shaped to provide particular cross-sections along the conductive paths; and has electrical connector means attached at the regions of the body so that current can be distributed through the body. The electrical resistance element is particularly useful as a heating element for air flowing through the pores in electrically powered room space heaters, hair dryers, hand dryers and the like and can also function as a self-cooling resistor.

Abstract: An improved method is described for thermally bonding contacting pieces of a thermoplastic material provided in a variable volume confined space surrounded by a combustible gas. The combustible gas is ignited and explosion diffused externally of the pieces of thermoplastic material and thus heats the pieces without damage sufficiently to produce interbonding when the heated pieces are compacted in the confined space. The heated pieces are compacted isostatically or non-isostatically using various apparatus which reduce the volume of the confined space. Preferably a moveable piston is provided in a cylinder to form the confined space for the pieces. The driving means for the piston can be a combustible gas which is ignited or non-combustible gas under pressure or a resilient means or other mechanical means. The products of the method are in the form of a porous mass composed of the interbonded pieces which are undamaged by the explosion.

Abstract: Novel activated carbon reticulated or unreticulated structures with interconnected cells are described. The carbon skeletal structures which are activated are derived from the carbonization of a parent homogeneous alloy of a furan resin with a polyurethane resin as a foam structure or as a skeletal structure with the foam membranes removed. Activation of the carbon structure during or after carbonization, is in contact with an oxidizing agent. The resulting activated carbon structures have unexpectedly high compressive strengths coupled with high activated surface areas per unit mass and volume and are particularly useful as adsorbents for chemicals in solution or as a gas.

Abstract: A method for preparing reticulate thermoset resin structures is described. Thermoset or thermosettable resin containing foams, prepared by a method wherein thin membranes dividing contiguous cells in a thin membraned, thick stranded thermoset or thermosettable resin foam with interconnected cells are produced, and are thermally reticulated. The foams are preferably thermally reticulated by providing a combustible gas mixture inside the cells of the foam and then igniting the mixture to destroy the foam membranes. The thermosettable or thermoset reticulate resin structures so produced are particularly useful for preparing carbon structures with the same geometry by heating at elevated temperatures under reducing, inert or vacuum conditions.

Abstract: An improved method is described for thermally bonding contacting pieces of a thermoplastic material provided in a variable volume confined space surrounded by a combustible gas. The combustible gas is ignited and explosion diffused externally of the pieces of thermoplastic material and thus heats the pieces without damage sufficiently to produce interbonding when the heated pieces are compacted in the confined space. The heated pieces are compacted isostatically or non-isostatically using various apparatus which reduce the volume of the confined space. Preferably a moveable piston is provided in a cylinder to form the confined space for the pieces. The driving means for the piston can be a combustible gas which is ignited or non-combustible gas under pressure or a resilient means or other mechanical means. The products of the method are in the form of a porous mass composed of the interbonded pieces which are undamaged by the explosion.

Abstract: A reticulated anisotropic porous carbon structure composed of bent or crimped interconnected and continuous strands is described. The structure is isomorphic with the compression bent strands of the flexible reticulated polyurethane structure from which it is derived. The structure compression can be sufficient for interbonding of the bent strands which overlay each other or the bent strands can be essentially free of bonding to adjacent strands. The carbon structure is derived by providing a compressed reticulated anisotropic polyurethane structure composed of the bent strands which is then infused with a liquid thermosetting resin or resin solution or resin precursor, removing any excess liquid resin or resin precursor or resin solution from the surfaces of the strands; and then carbonizing the infused strands at an elevated temperature.

Abstract: A rapid method for forming vitreous carbon foams from flexible polyurethane foams having membranes dividing contiguous cells, which faithfully reproduces the geometry of the uncarbonized polyurethane foams, by infusing the polyurethane foams with substantially unresinified or unpolymerized furfuryl alcohol which is capable of resinification at temperatures above room temperature is described. An important step in the method which permits rapid carbonization without cracking and which is essential to faithful foam geometry reproduction is the substantial removal of the liquid non-infused furfuryl alcohol from the polyurethane foam surfaces after the infusion or swelling step. The carbonized foam is in the form of vitreous, disordered or glassy carbon and is particularly useful for corrosive and/or high temperature applications such as insulation, corrosion resistant chemical processing components and the like.

Abstract: The preparation of three dimensional skeletal structures using the step of deforming rounded beads to form a mold or matrix is described. A filler material is introduced and then rigidified to form the skeletal structure. The deformable beads are composed of materials which deform upon compression or expansion due to pressure from adjacent beads and included, for instance, metals, waxes, salts, polymers, and ceramic compositions in their plasticly deformable states. The filler material which rigidifies to form the skeletal structure can be composed of solidifiable materials such as metals, polymers, or ceramic compositions. The solid material volume of the skeletal structure so formed upon removal of the beads is between about two percent (2%) to twenty percent (20%) of a corresponding volume of a non-skeletal solid material.

Abstract: The preparation of three dimensional skeletal structures using the step of deforming rounded beads to form a mold or matrix is described. A filler material is introduced and then rigidified to form the skeletal structure. The deformable beads are composed of materials which deform upon compression or expansion due to pressure from adjacent beads and included, for instance, metals, waxes, salts, polymers, and ceramic compositions in their plasticly deformable states. The filler material which rigidifies to form the skeletal structure can be composed of solidifiable materials such as metals, polymers, or ceramic compositions. The solid material volume of the skeletal structure so formed upon removal of the beads is between about 2% to 20% of a corresponding volume of a non-skeletal solid material. The corresponding porosities representing the interconnected void volumes are between about 80% and 98% of a corresponding volume of a non-skeletal solid material.

Abstract: A method for rounding sharp edged tube lips and for cleaning of dialysis units, such as artificial kidneys, of the type where multiple tube ends are sealed in place at end surfaces to be cleaned in the unit, is described. The method involves the transient thermal treatment of the tube lips and the end surfaces adjacent the lips of the unit while the inside of each of the tubes is filled with a noncombustible fluid which shields the tubes from the thermal treatment. The resulting heat-polished rounded tube lips in the unit provide improved dialyzate fluid flow. In artificial kidneys, damage to cells in blood being dialyzed is reduced and reduction of particulate matter introduced into the blood is accomplished.

Abstract: A sealed system process for the elimination (destruction or removal) of superfluous projections, such as unwanted burrs and sharp edges, on shaped or fabricated articles of manufacture, particularly those produced by mechanical shaping or fabricating, by treatment with transient elevated gaseous temperatures in a sealed and confined space. The transient elevated gaseous temperatures in the sealed and confined space are produced, for instance, by the ignition or other suitable reaction initiation of various compositions which are exothermic in the sealed and confined space, by the rapid and substantially adiabatic compression of a gas in the sealed and confined space or by some other manner such as by the rapid movement of a heated gas wave under pressure through the sealed and confined space, such as exists in a shock wave, so that the transient elevated gaseous temperatures are produced.