Abstract: A process is disclosed for making a highly fluorinated aromatic compound by contacting a perfluorocycloalkane, such as perfluorodecahydronaphthalene, with a complex of a metal from Groups IA and IIA of the Periodic Table and an organic electron acceptor. The reaction is carried out in an organic solvent and under reducing conditions which are relatively moderate. Best results are obtained using a perfluorocycloalkane having 2-4 condensed rings and a complex of either sodium or lithium and benzophenone thereby making a perfluorinated condensed ring aromatic compound such as perfluoronaphthalene or perfluorophenanthrene.

Abstract: The present invention is a concentration swing adsorption process for separating a liquid phase feedstock comprising a more adsorbable component (A) and a less adsorbable component (B) with respect to an adsorbent. The process is operated in a system comprising a single or a plurality of adsorption columns containing the adsorbent which are operated in cycle in a predetermined sequence. The following operational steps are performed in the order recited in each of the adsorption columns in its turn. Feedstock is passed through the adsorbent and the more adsorbable component (A) is selectively adsorbed while a stream enriched in component (B) is discharged from the adsorption column. The adsorbent is rinsed in a direction co-current to the feedstock with the more adsorbable component (A) whereby the less adsorbable component (B) is displaced from the adsorbent and a stream comprising a mixture of the more adsorbable component (A) and the less adsorbable component (B) is withdrawn from the adsorption column.

Abstract: The method for producing the disclosed material comprises chemical vapor depositing on the substrate a substantially columnar, intermediate layer of tungsten and chemical vapor depositing on the intermediate layer a non-columnar, substantially lamellar outer layer of a mixture of tungsten and tungsten carbide. The tungsten carbide comprises W.sub.2 C, W.sub.3 C, or a mixture of both wherein the ratio of the thickness of the tungsten intermediate layer to the thickness of the outer layer is at least: (a) 0.35 in the case of tungsten plus W.sub.2 C in the outer layer, (b) 0.6 in the case of a mixture of tungsten and W.sub.3 C in the outer layer and (c) 0.35 in the case of mixtures of tungsten and W.sub.2 C and W.sub.3 C in the outer layer. The chemical vapor deposition steps are carried out at pressures within the range of 1 Torr to 1,000 Torr and temperatures within the range of about 300.degree. to about 650.degree. C.

Abstract: A rapid burning propellant charge for applications including igniters, launch eject motor, and gas generators for automobile air bags. The propellant charge comprises a reticulated substrate having a quantity of interconnected ligaments and a coating of solid propellant material on the ligaments. In order to provide a large amount of surface area for a fast burn time, interstices are between coated ligaments to define propellant surface area for combustion. In applications where minimum smoke is desired, the reticulated substrate is preferably composed of carbon, graphite, or a non-combustible material, and the solid propellant material is preferably a minimum smoke type.

Abstract: This invention relates to polyepoxide resins cured with an amine composition containing 1-methyl-2,6-cyclohexanediamine. The resulting polyepoxide resins generally are more easily processable and have improved thermal stability, greater elongation and enhanced fracture toughness.

Abstract: Ethylidene bisamide is produced by the reaction of vinyl acetate with a primary carboxylic acid amide over a catalytic amount of a salt of palladium (II), platinum(II) or mercury(II). The reaction is carried out in the presence of an aliphatic or arylaliphatic alcohol in a concentration greater than 0.01 equivalents based upon the limiting reagent.

Abstract: A method for profiling the chemical structure and elemental composition as a function of distance below the exterior surface of a thermoplastic article, and more particularly, to a method for determining the depth of permeation of a modifier into the interior of a thermoplastic article which has been treated with the modifier. The method utilizes a pulsed ultraviolet energy source having a fluence level and pulse duration sufficient to ablate material from the article's exterior surface to a series of successive predetermined distances below the exterior surface to expose successive interior surfaces while causing essentially no physical or chemical damage to each respecting interior surface exposed by ablation. The elemental and chemical compositions of each successive interior surface are analyzed by a surface sensitive spectrographic technique and the spectrographic results are compared to determine the depth of modifier permeation within the thermoplastic article.

Abstract: A crude helium product is produced from a natural gas stream containing helium by rectification of the feed gas in a dephlegmator heat exchanger. The process is fully auto-refrigerated, and is capable of achieving a helium recovery of 99% without the use of a recycle compressor or a heat pump compressor. A nitrogen product stream can be produced by addition of a second rectification circuit in the dephlegmator heat exchanger.

Abstract: A low temperature chemical vapor deposition process comprising heating in a chemical vapor depositon reactor a substrate upon which deposition is desired to a temperature of from about 550.degree. C. to about 750.degree. C. in a chemical vapor deposition reactor having a pressure of from about 0.1 torr to approximately atmospheric pressure, introducing into the reactor a silicon-containing feed and optionally an oxygen containing feed, said silicon containing feed consisting essentially of one or more compounds having the general formula ##STR1## wherein: R.sub.1, R.sub.2, R.sub.3 and R.sub.4 are hydrogen, azido or C-2 to C-6 alkyl, aryl or C-7 to C-10 aralkyl groups, at least one but not more than three of R.sub.1, R.sub.2, R.sub.3 and R.sub.4, being azido, and maintaining the temperature and pressure to cause a film of silicon nitride, silicon oxynitride or silicon dioxide to deposit is disclosed.

Abstract: The present invention is a class of polymeric membranes formed from aromatic polyarylates derived from dicarboxylic acid chlorides and conformationally rigid cyclohexyl bisphenols having halo or methyl substituents on all positions ortho to the hydroxy functions. These polarylate membranes exhibit high gas permselectivities and are useful in various gas separation applications.

Abstract: A composite of a rigid, glassy, permeable membrane of a silyl or germyl-containing polyacetylene and a thin surface layer of a plasma polymerized monomer having pendant nitrogen heterocycles is provided; the composite has high flux and selectivity and is particularly useful for separating gas mixtures containing at least two components having different permeabilities through the composite structure.

Abstract: Carbon black is produced from a pyrolyzed hydrocarbon wherein pyrolysis is effected by combusting a synthesis gas containing hydrogen and carbon monoxide. The synthesis gas is produced from reforming a hydrocarbon fuel, wherein the reformation is heated by combusting carbon black effluent tail gas or indirect heat exchange of the hot tail gas.

Abstract: A urethane catalyst which is an imidazole ether compound of the formula ##STR1## where R.sub.1, R.sub.2 and R.sub.3 are independently hydrogen, methyl or ethyl and R.sub.4 is ethylene, n-propylene or isopropylene.The imidazole compounds provide for delayed initiation while maintaining an acceptable cure time in the production of polyurethane foam.

Abstract: The present invention is a process for prefractionating a pressurized, helium-containing feed gas mixture (typically containing helium, natural gas and nitrogen) to produce a helium-enriched stream which comprises the following steps: (a) the pressurized, helium-containing feed gas mixture is liquefied and subcooled by indirect heat exchange; (b) the liquefied, subcooled, pressurized, helium-containing feed gas mixture is expanded whereby it is partially vaporized, thus producing a partially vaporized frationation feed stream; (c) the partially vaporized frationation feed stream is stripped in a cryogenic distillation column thereby producing as an overhead, the helium-enriched stream, and a bottoms liquid, the helium-lean stream; and (d) the cryogenic distillation column is reboiled by vaporizing at least a portion of the helium-lean stream. The present invention is also applicable as an improvement to a process for the production of a crude helium product (i.e.,>30 vol % helium).

Abstract: A residue-free fluxing process wherein the active fluxing agent comprises a .beta.-diketone or .beta.-ketoimine ligand. Such ligands react with surface metal oxides on workpieces to be soldered to form volatile metal-ligand complexes as reaction products which are sublimed from the surface leaving essentially no residue on the workpieces. The fluxing agents can be utilized in gas-phase processes wherein the workpieces are contacted with an effective amount of one or more ligands which are dispersed in a carrier gas or solvent or by incorporating the ligands into an alloy-vehicle mixture for use as conventional creams or pastes. The invention eliminates the need for post-reflow cleaning using solvents since no flux residue remains on the workpieces to be soldered following volatilization of the metal-ligand complex.

Abstract: A vinyl acetate copolymer comprising the following general structure: ##STR1## wherein R is hydrogen or methylX is an organic linking group such as ##STR2## R.sup.1 is C.sub.1 -C.sub.4 alkyl; R.sub.f is a perfluorinated alkyl or poly(alkyleneoxy) group;m is 0 or 1;y is 50-99.999 mole %; andz is 0.001-50 mole %.The vinyl acetate copolymer is hydrolyzed to provide a vinyl alcohol copolymer that has excellent solvent barrier properties.

Abstract: The present invention is a class of semi-permeable polymeric membranes and processes for using such membranes to separate one or more components of a gas mixture. The membranes are formed from aromatic polyimides derived from reaction of a 9,9-bis-(3,4-dicarboxyphenyl)-fluorene dianhydride and at least one aromatic diamine. These polyimide membranes exhibit high gas perm-selectivities and are especially useful in effecting the separation of oxygen and nitrogen from air.

Abstract: An igniter which is removably insertable in a rocket motor nozzle throat. The igniter includes a sleeve which has a body portion and a plurality of flexible and frangible tab members extending axially from one end of the body portion and spaced circumferentially thereabout and which have first portions which in combination define a diameter which is greater than the nozzle throat diameter. The frangible portions of the tab members in combination define an outer diameter which is substantially equal to the throat diameter. The body portion of the sleeve has a diameter which is greater than the throat diameter. The sleeve is insertable in the nozzle throat by flexing the tab members so that the first portions clear the throat and so that the frangible portions of the tab members are disposed in the throat. The tab members, in combination, have an inner diameter which is substantially equal to the inner diameter of the body portion of the sleeve.

Abstract: A process and apparatus are described for recycling dust generated in rotary kiln processes such as cement manufacture. The invention resides in enriching the atmosphere in the kiln with oxygen so as to increase the heat generated and accommodate the introduction of recycled kiln dust. The oxygen enrichment and dust recycle are balanced so that the kiln operates to produce the same quality product as it did without either oxygen enrichment or dust recycle.

Abstract: Fluorinated .beta.-ketoimine ligands and highly volatile .beta.-ketoiminato metal complexes of the ligands are synthesized by silylating a fluorinated .beta.-diketone to form a silylenolether, and subsequently reacting the silylenolether with a primary amine to form the desired ligand having the structural formula: ##STR1## wherein R.sub.1 and R.sub.2 are independently linear or branched perfluorinated, C.sub.1 -C.sub.8 alkyl groups and R.sub.3 is a phenyl or C.sub.1 -C.sub.8 alkyl, hydroxyalkyl, or ether group, all of which can be partially or fully fluorinated. The corresponding metal complex is formed by treating the ligand with a metal halide.