Abstract: This invention relates to an improved method for curing polyepoxide resins at elevated temperature and particularly to a method for reducing the time required to effect cure of thermosetting resins at elevated temperature without sacrificing performance. In the basic process, an epoxide resin comprising a polyglycidyl ether of a polyhydric phenol is contacted with methylenedianiline or derivative thereof, e.g., methylenedianiline and di(3-methyl-4-aminophenyl)methane in an amount sufficient to effect cure of the polyepoxide resin at an initial temperature and then raised to a final cure temperature. The improvement for reducing the time necessary for cure comprises:effecting an initial and partial cure of the epoxy resin at a temperature between 90.degree. and 130.degree.

Abstract: The present invention is directed to an at least binary exchanged X-zeolite having lithium and a divalent cation selected from the group consisting of cobalt, copper, chromium, iron, manganese, nickel and mixtures thereof in a ratio of preferably 5% to 50% of the divalent cation and 50% to 95% lithium. Theses adsorbents are useful in a process for separating nitrogen from gas mixtures containing nitrogen and less strongly adsorbed components such as oxygen, hydrogen, argon or helium.

Abstract: A method has been developed for the removal of silicon nitride and silicon dioxide, or other semiconductor materials from a surface of a wafer or CVD reactor. The method uses NF.sub.3, mixed with an electropositive diluent, preferably argon, at a given range of concentration, pressure, flowrate, and power to obtain the fastest possible etch rates. The etch rates of the film being processed can be caused to increase even as the concentration of NF.sub.3 in the diluent is decreased by choosing the proper diluent and operating conditions. Not only does this method increase the etch rate, thereby increasing the throughput of the reactor using this process, it also accomplishes this task at low concentrations of NF3 resulting in a lower cost.

Abstract: This invention relates to an improved method for curing polyepoxide resins at elevated temperature and particularly to a method for reducing the time required to effect cure of thermosetting resins at elevated temperature without sacrificing performance. In the basic process, an epoxide resin comprising a polyglycidyl ether of a polyhydric phenol is mixed with cycloaliphatic amine, e.g., di(4-aminocyclohexyl)methane, di(4-amino-3-methylcyclohexyl)methane, and isophoronediamine in an amount sufficient to effect cure of the polyepoxide resin at an initial temperature and then raised to a final cure temperature. The improvement for reducing the time necessary for cure comprises:effecting an initial and partial cure of the epoxy resin at a temperature between 60.degree. and 100.degree. C.

Abstract: A process for separating a feed gas mixture into a more strongly adsorbable component and a less strongly adsorbable component in a plurality of adsorbent beds containing an adsorbent selective for the more strongly adsorbable component with two cocurrent depressurizations, first to provide product and then to provide a purge gas, and using a combination of less strongly adsorbable component and feed gas mixture to repressurize the adsorbent bed. Oxygen product can be recovered from air at high recovery using the process.

Abstract: Amine functional polymers which are terpolymers made up of randomly linked units of amidine or amidinium formate, N-vinylformamide and either vinylamine or vinylammonium formate are prepared by aqueous hydrolysis of poly(N-vinylformamide) at a temperature in the range of 90.degree. to 175.degree. C., preferably in the presence of a minor amount of ammonia or volatile amine. Best conversions and good control of polymer structure are obtained at 140.degree. to 160.degree. C. with a small concentration of ammonia or alkylamine. Formation of poly(vinylammonium formate) containing no other salts or ionic coproducts is realized by degassing the hydrolyzate to remove ammonia or amine from the polymer solution. The poly(vinylammonium formate) affords distinct advantages in the production of salt-free polymers by catalytic decomposition of impurities. Poly(vinylamines) containing significant amounts of amidine functionality offer advantages in applications where increased basicity is required.

Abstract: The present invention discloses an improved process for producing plastic containers with excellent resistance to permeation by solvents such as hydrocarbons, hydrocarbon fuels, and hydrocarbon fuels with organic additives including lower alkanols and ethers consistently and reliably. The process is related to a multi-step treatment of plastic containers in a controlled manner with fluorine containing gases while blow molding them. In the process of the present invention, a parison is formed from a pre-heated thermoplastic material, expanded within a closed mold by means of an inflating gas for conforming the parison to the shape of the mold, and subjected to multiple fluorination treatment steps to effect fluorination of the interior surface of the parison. In the first step of the multi-step fluorination treatment the parison is pressurized with a reactive gas containing from about 0.05 to about 0.

Abstract: This invention relates to a process for producing a nonequilibrium distribution of methylamines by the catalyzed reaction of methanol and/or dimethyl ether with ammonia and by the catalytic reforming of a methylamine containing feedstock. One process selectively affords a reaction product enriched in mono and dimethylamines and low in trimethylamine, at high conversion of methanol or dimethylether. A variation of the process effects reforming a methylamine containing feedstock, optionally containing ammonia over a catalyst. The key to achieving this low TMA selectivity at high conversion resides in the use of a microporous zeolite, preferably chabazite, catalyst having a geometric selectivity index (GSI) less about 3, a shape selectivity index (SSI) greater than about 5 and a sorption capacity for 1-PrOH of at least 0.5 mmol/g.

Abstract: Method for the treatment of cellulosic pulp in which pulp is distributed upward through a vertical reactor using a unique conical distributor and is discharged using a unique dilution method to eliminate plugging. The system is particularly useful for delignifying virgin wood pulps or decolorizing pulps made from waste paper materials.

Abstract: An oxygenated organic liquid product and a fuel gas are produced from a portion of synthesis gas comprising hydrogen, carbon monoxide, carbon dioxide, and sulfur-containing compounds in a integrated feed treatment and catalytic reaction system. To prevent catalyst poisoning, the sulfur-containing compounds in the reactor feed are absorbed in a liquid comprising the reactor product, and the resulting sulfur-containing liquid is regenerated by stripping with untreated synthesis gas from the reactor. Stripping offgas is combined with the remaining synthesis gas to provide a fuel gas product. A portion of the regenerated liquid is used as makeup to the absorber and the remainder is withdrawn as a liquid product. The method is particularly useful for integration with a combined cycle coal gasification system utilizing a gas turbine for electric power generation.

Abstract: A method for white liquor oxidation in a kraft mill utilizes a two-stage selective oxidation system in which the first stage is operated to remove sulfide while the second stage is operated to oxidize a significant fraction of the remaining oxidizable sulfur compounds to sulfate. The resulting selectively oxidized white liquor products are used as alkali sources for various process steps in the mill. Optionally, white liquor can be oxidized in a single stage to convert a significant fraction of the oxidizable sulfur compounds to sulfate. Methods for controlling the selective oxidation process are disclosed.

Abstract: A closed-loop mixed refrigerant cycle provides efficient low-level refrigeration for recovering ethylene from a mixed gas feed. Compressed mixed refrigerant vapor is condensed at -20.degree. F. to -50.degree. F. and is subcooled to -175.degree. F. to -225.degree. F. by indirect heat exchange with cold H.sub.2, methane, and expander streams from elsewhere in the ethylene plant. A portion of the subcooled refrigerant may be flashed to provide additional subcooling of the main mixed refrigerant stream. Subcooled mixed refrigerant is subsequently flashed to provide very low temperature level refrigeration for feed condensation and demethanizer overhead condenser duties.

Abstract: Refrigeration is provided in an ethylene recovery plant by an open-loop mixed refrigeration cycle which utilizes components present in the ethylene-containing feed gas as the mixed refrigerant. Refrigeration is provided by subcooled mixed refrigerant at -175.degree. to -225.degree. F. for the demethanizer overhead condenser and for initial cooling and condensation of the ethylene-containing feed gas. Overall ethylene recoveries of up to 99.9% can be achieved at reduced power consumption compared with conventional ethylene recovery cycles. In addition, significant capital savings can be realized due to the simplification of equipment with the open-loop mixed refrigerant cycle.

Abstract: A turbocharged or supercharged internal combustion motive system for utilization of gaseous fuel stored as a liquid wherein the liquefied gaseous fuel is vaporized and warmed at least partially with heat removed from the compressed intake combustion air in the turbocharger or supercharger aftercooler. In a preferred embodiment, the compressed intake combustion air is first cooled in an aftercooler against an ambiently cooled coolant and is subsequently cooled in further aftercooler heat exchange passages against an intermediate coolant which transfers heat removed from the compressed intake combustion air to the liquefied gaseous fuel.

Abstract: Vinylamide oligomers having molecular weights between about 280 and 7,500 are prepared by the cationic polymerization of vinylamides in the presence of a Lewis acid at a temperature between -100.degree. and 100.degree. C. The resultant vinylamide oligomers are characterized in that they have a proton initiating group at one end and an aldehyde equivalent at the other end. These vinylamide oligomers can optionally be hydrolyzed under acidic or basic conditions to form the corresponding vinylamine oligomers.

Abstract: A reactor system is disclosed for the treatment of cellulosic pulp in which pulp is distributed upward through a vertical reactor using a unique conical distributor and is discharged using a unique dilution method to eliminate plugging. The system is particularly useful for delignifying virgin wood pulps or decolorizing pulps made from waste paper materials.

Abstract: N,N'-Di-(branched alkyl)-alkylenediamine-bis-p-aminobenzamides are useful as chain extenders in the manufacture of polyurethane-urea elastomers. These compositions have remarkably uniform reactivities but can be varied structurally to achieve a range of processibility characteristics by altering the melting points of the chain extenders. The preferred compounds melt in a range of 50.degree. to 175.degree. C. while exhibiting t.sub.5000 reactivities of about four minutes. The combination of processing characteristics, reactivities and physical properties of the elastomer products offers advantages not available in commonly used diamine chain extenders of the prior art.

Abstract: Resins which comprise polymers which contain multiple acetal groups have been developed which are useful for crosslinking and adhesion promotion in coating and adhesive applications. The polymers which make up these resins are prepared by the addition of aminoacetals to polymers containing anhydride functionality. The polymers are modified by titration with ammonia or a primary or secondary amine which solubilizes the polymer in aqueous systems.

Abstract: Resins which comprise polymers which contain multiple acetal groups have been developed which are useful for crosslinking and adhesion promotion in coating and adhesive applications. The polymers which make up these resins are prepared by the addition of aminoacetals to polymers containing anhydride functionality. The polymers are modified by titration with a tertiary amine or alkali base.

Abstract: A coated carbon body having improved resistance to high temperature oxidation and a method for producing the coated carbon body are described. The coated carbon body comprises a carbon body, an intermediate glass forming coating within said converted layer, and an outer refractory coating on the intermediate coating. The body has a converted porous layer formed by etching and reacting the body with gaseous boron oxide and the resulting converted layer contains interconnecting interstices and boron carbide formed by the reaction of the boron oxide and the carbon body. The method comprises contacting a carbon body with boron oxide at an elevated temperature sufficient to cause the reaction between the carbon body and boron oxide to form a converted porous layer which contains interconnecting interstices in the body and boron carbide and then applying the intermediate glass forming coating over the converted layer and an outer refractory coating over the intermediate coating.