Abstract: A high quality non-single-crystal silicon alloy material including regions of intermediate range order (IRO) silicon alloy material up to but not including the volume percentage required to form a percolation path within the material. The remainder of the material being either amorphous or a mixture of amorphous and microcrystalline materials. The materials were prepared by CVD using differing amounts of hydrogen dilution to produce materials containing differing amounts of IRO material. Preferably the material includes at least 8 volume percent of IRO material.

Abstract: Trichlorosilane for producing polycrystal silicon and tetrachlorosilane for producing trichlorosilane are storaged under hydrogen gas as a sealing gas. High-purity polycrystal silicon is provided.

Abstract: A method for producing tri- or higher-silane from mono- or lower-silane characterized by reacting a lower silane in the first reaction zone and reacting a portion or all of the reaction product thereof in a reaction zone of the second or subsequent reaction zone.

Abstract: A process for the production of monosilanes from the high-boiling residue resulting from the reaction of hydrogen chloride with silicon metalloid in a process typically referred to as the "direct process." The process comprises contacting a high-boiling residue resulting from the reaction of hydrogen chloride and silicon metalloid, with hydrogen gas in the presence of a catalytic amount of aluminum trichloride effective in promoting conversion of the high-boiling residue to monosilanes. The present process results in conversion of the high-boiling residue to monosilanes. At least a portion of the aluminum trichloride catalyst required for conduct of the process may be formed in situ during conduct of the direct process and isolation of the high-boiling residue.

Abstract: A process for the preparation of substantially polycrystalline silicon carbide fibers is provided. The fibers may be fabricated to have a small diameter and are thermally stable at high temperatures. The process is carried out by initially forming fibers from a preceramic polymeric precursor comprising methylpolysilane resins. The fibers are then infusibilized to render them nonmelting followed by a pyrolysis step in which the fibers are heated to a temperature in excess of 1600.degree. C. in a nonoxidizing atmosphere to form substantially polycrystalline silicon carbide fibers. The substantially polycrystalline silicon carbide fibers which are formed by the process of the present invention have at least 75% crystallinity and have a density of at least about 2.9 gm/cm.sup.3. The polymeric precursor or the fibers contain, or have incorporated therein, at least about 0.2% by weight boron.

Abstract: A solution of hydride in liquid nitrogen, the hydride being one that is in gaseous phase at atmospheric pressure and ambient temperature. The concentration of hydride in the liquid nitrogen is comprised between 0.05 and 10 mol %, preferably between 0.05 and 2 mol %, and more preferably between 0.1 and 0.3 mol %. The hydride is selected from the group consisting of arsine, germane, phosphine (PH.sub.3), diborane and silane (SiH.sub.4) and is preferably silane. Atmospheres prepared from these solutions are useful in the thermal treatment of metals, or for surface treatment, particularly of polymeric or metallic surfaces.

Abstract: Aqueous hydrides including a metal, a metal hydroxide and water and a method of manufacture therefor are provided. The method includes a reaction which does not require precise stoichiometric proportions of metal, alkali hydroxide and water. The specific gravity of the reaction mixture is monitored and adjusted where appropriate during the reaction process. Temperature and rate of reaction are controlled to prevent formation of silicates. Aqueous by, rises produced in accordance with the invention exhibit polymer characteristics and are suitable for use as coatings, reducing viscosity, sequestering agents, emulsion agents, surfactants, detergents and the like.

Abstract: An improved process for contacting hydrogen gas and tetrachlorosilane in a reactor comprising a pressurizable shell having located therein a reaction vessel forming a substantially closed inner chamber for reacting the hydrogen gas with the tetrachlorosilane. The improvement comprises feeding to an outer chamber between the pressurizable shell and the reaction vessel a gas or gaseous mixture having a chlorine to silicon molar ratio greater than about 3.5. The improvement reduces the concentration of hydrogen and tetrachlorosilane in the outer chamber that results from leakage of these gases from the substantially closed inner chamber and the detrimental reactions associated with such leakage on structural elements and performance of the reactor.

Abstract: A process for the hydrogenation of chlorosilanes. The process comprises contacting a chlorosilane with aluminum and a hydrogen source selected from a group consisting of hydrogen gas and gaseous hydrogen chloride in the presence of a catalyst. The catalyst is selected from a group consisting of copper and copper compounds, tin and tin compounds, zinc and zinc compounds, and mixtures thereof.

Abstract: Metal hydride compositions comprise a mixture of (a) from about 1 to about 10 parts, by molecular weight, of at least one metal selected from the group consisting of silicon, aluminum, tin and zinc; (b) from about 1 to about 3 parts, by molecular weight, of an alkali metal hydroxide; and (c) from about 5 to about 10 parts, by molecular weight, of water. These compositions may be used in various applications, including, among others, methods for separating coal fines from coal fine waste slurries, methods for cleaning and desludging hydrocarbon storage tanks, methods for providing fire-retardant properties to composite materials and methods for providing corrosion protection to metal parts.

Abstract: Organic-solvent soluble magnesium hydrides or formulas ##STR1## are prepared by catalytically hydrogenating finely powdered magnesium, optionally in the presence of a magnesium halide, in an organic solvent in the presence of their MgH.sub.2 -free counterparts in whichQ is an alkyl, alkenyl, alkoxy, dialkylamino, aralkyl, aryl or diarylamino group, each with up to 18 carbon atoms,R is an alkenyl, aralkyl or aryl group, each with up to 18 carbon atoms,X is chlorine, bromine, or iodine, ##STR2## is a chelating ligand, E is --CH.sub.2, --N(R)-- or --O--,is an alkylene radical of the formula --(CH.sub.2).sub.p,D is a dialkylamino, diarylamino or alkoxy group, each with up to 18 carbon atoms,M is aluminum or boron,m is 1, 2, or 3, and1<n.ltoreq.50.

Abstract: There is disclosed a method for producing a polysilane which comprises reacting a hydrosilane compound in the presence of an organolanthanoid complex.

Abstract: The present invention provides a method of removing impurities from a stream of silane, SiH.sub.4. Most notably, the present invention provides a method of removing ethylene from a silane stream by converting the ethylene to ethylsilane in the presence of a molecular sieve and distilling the desired silane from the ethylsilane contaminant.

Abstract: Improved molecular sieves and processes for treatment of molecular sieves which permit use for separation of ethylene and silane without attending formation of ethylsilane. Such treatment includes treatment of sieves with silane at an effective temperature, pressure and time.

Abstract: The present invention is a process for the production of silanes from the contact of silicon metal or a silicon containing material with hydrogen chloride. The described process employs a metal or metal compound on a solid support as a catalyst which increases the production of tetrachlorosilane. The metal or metal compound is selected from a group consisting of palladium and palladium compounds, rhodium and rhodium compounds, platinum and platinum compounds, iridium and iridium compounds, tin and tin compounds, nickel and nickel compounds, and aluminum and aluminum compounds. The process is run at a temperature of about 250.degree. C. to 500.degree. C.

Abstract: The present invention is a process for the production of silanes from the contact of hydrogen chloride with silicon. The silicon may be in the form of silicon metal or a silicon containing material. The described process employs a catalyst which increases the yield of tetrachlorosilane. The catalyst is selected from a group consisting of tin and tin compounds, nickel and nickel compounds, arsenic and arsenic compounds, palladium and palladium compounds, and mixtures thereof. The process is run at a temperature of about 250.degree. C. to 500.degree. C.

Abstract: A system for generating a gaseous polyhydridic Group IV-VI compound, comprising a vessel containing a solid precursor metal compound for the polyhydridic Group IV-VI compound, and a source of a fluid-phase protonic activator compound reactive with the precursor compound to yield as reaction product (a) the polyhydridic compound and (b) a solid reaction product compound containing the metal moiety, e.g., a non-volatile metal salt, together with means for flowing the activator compound from the source thereof to the vessel containing the solid precursor compound. The precursor compound may suitably comprise a metal moiety such as lithium, sodium, magnesium, zinc, potassium, aluminum, and intermetallic complexes and alloys thereof. In a preferred aspect, wherein arsine is generated, the precursor compound may suitably comprise a metal arsenide, and the protonic activator compound is water or an acid such as hydrogen chloride.

Abstract: Preceramic polysilazanes which (1) are composed of silicon, nitrogen, and hydrogen, (2) can be isolated and redissolved in common organic solvents, and (3) are capable of providing a high ceramic yield when pyrolyzed are prepared by reacting a mixture of one molar proportion of a tetrahalosilane, preferably tetrachlorosilane, and at least 4.5 molar proportions of a dihalosilane, preferably dichlorosilane, in an organic solvent. Ceramics obtained from the polysilazanes are nanoporous, amorphous silicon nitride ceramics having high purity.

Abstract: The described invention is a process for preparing silanes from the reaction of solid silicon monoxide with aromatic halides. The solid silicon monoxide is reacted with the aromatic halide in the presence of a catalyst which can increase the conversion of silicon monoxide to silanes, and partially select for arylsilane products. The process may employ an activation step in which the solid silicon monoxide is activated by heating in an inert atmosphere. Activation of the solid silicon monoxide can increase silicon conversion and increase selectivity for arylsilane products.

Abstract: The present invention is a process for separating particulate silicon from a liquid by-product stream containing silanes. The liquid by-product stream comprising silanes and particulate silicon is atomized into a heated zone to effect vaporization of the liquid silanes, thus drying the particulate silicon. The dried particulate silicon is separated from the gaseous silanes by filtration or other suitable means. The separated solid and gaseous phases may be used as feed to the process generating the by-product stream or as a feed for other processes.

Abstract: A process for the dismutation of chlorosilanes is disclosed in which the latter are in the gas phase for 0.01-100 sec. at 55.degree.-100.degree. C. or in the liquid phase for 1-1000 sec. at 25.degree.-55.degree. C. conducted in the presence of a catalyst, which is either unformed or is present in the form of spherical pellets, and which consists of one of four different organopolysiloxane compounds, optionally cross-linked, which essentially carry an amino or ammonium group as a functional group.

Abstract: The present invention relates to soluble perhydrosiloxane copolymers of the formula [H.sub.2 SiO].sub.x [HSiO.sub.3/2 ].sub.y wherein the mole fractions x and y total 1. In addition, the present invention relates to the use of these novel copolymers as coating materials, especially for use on electronic devices.

Abstract: Process for preparing disilane, wherein a raw gas including monosilane, disilane, trisilane and impurities such as phosphine, hydrogen sulfide, arsine, disiloxane and higher siloxanes, undergoes a step of separation by distillation for the substantial elimination of the other compounds of silicon, except disiloxane, and the substantial elimination of phosphine, hydrogen sulfide and arsine impurities, wherein a final purification of the disilane takes place by selective adsorption on molecular sieves, in which one is a sieve of type 3 A and which is used for the elimination of the siloxanes and hydrogen sulfide and the other is a sieve of type 4 A for the elimination of phosphine and arsine.

Abstract: The invention relates to novel polysilazanes, the preparation thereof, the further processing thereof to form silicon nitride-containing ceramic material, and this material itself. In order to prepare the polysilazanes, dialkylaminoorganyldichlorosilanes of the formula RSiCL.sub.2 --NR'R' are reacted with ammonia. The polysilazanes can then be pyrolyzed to form silicon nitride-containing ceramic material. The polysilazanes according to the invention dissolve in customary aprotic solvents.

Abstract: A process for continuously preparing silane and a coproduct by reacting a metal hydride such as NaAlH.sub.4 with a silicon halide such as SiF.sub.4, utilizing, in conducting the reaction, equipment which includes, in series, a primary reactor, a secondary reactor and a separation zone. The metal hydride is reacted in the first reactor with less than a stoichiometric amount of the silicon halide, and the unreacted metal hydride is then passed to the second reactor wherein the remainder of the hydride is reacted in the secondary reactor, in which a stoichiometric excess of the silicon halide is added. The rate of silicon halide or metal hydride addition is governed by a temperature differential feed back from the reaction in the secondary reactor so that overall a stoichiometric or substantially stoichiometric operation is achieved.

Abstract: Improved processes for the production of silane. Hydridomagnesium chloride and trichlorosilane are reacted in an ether solvent to co-produce silane and magnesium chloride. Recycle schemes are presented for the recovery of magnesium values.

Abstract: The present invention is processes for preparing silanes from the reaction of silicon monoxide with hydrogen halides. In a first embodiment of the instant invention, silicon monoxide is reacted with a hydrogen halide to produce silanes and halosilanes. In a second embodiment of the instant invention, the silicon monoxide is activated by heating in an inert atmosphere prior to contact with the hydrogen halide. In a third embodiment of the instant invention, a catalyst is employed which enhances conversion of silicon monoxide to silanes and modifies process selectivity for silane products. The catalyzed process can be run with activated or non-activated silicon monoxide.

Abstract: The present invention is a process for preparing silanes from the reaction of solid silicon monoxide with organic halides. The solid silicon monoxide is reacted with the organic halide in the presence of a catalyst which can increase the conversion of silicon monoxide to silanes and partially select for the type of silanes produced. The process may employ an activation step in which the solid silicon monoxide is activated by heating in an inert atmosphere. Activation of the silicon monoxide can increase silicon conversion and alter the type of silanes produced.

Abstract: Silated polysaccharides having 0.005 to 2.0 silyl molar substitution per anhydrosaccharide unit form water resistant films when cast from aqueous solution and dried in the presence of atmospheric carbon dioxide. These films are soluble in aqueous caustic. A preferred water soluble polymer is a cellulose ether with 0.005 to 1.0 silyl substitution.

Abstract: Silated polysaccharides having 0.0005 to 2.0 silyl molar substitution per anhydrosaccharide unit form water resistant films when cast from aqueous solution and dried in the presence of atmospheric carbon dioxide. These films are soluble in aqueous caustic. A preferred water soluble polymer is a cellulose ether with 0.005 to 1.0 silyl substitution.

Abstract: Silane can be adsorbed by KOH on alumina. This discovery can be used to remove silane from other gases, e.g. hydrogen.

Abstract: Impure gaseous silane containing such impurities as, in particular, phosphines and arsines, is purified, whether by chemisorption and/or physical adsorption, by contacting such silane gas with a sorption mass that includes cooper values, e.g., a copper cation-exchanged molecular sieve.

Abstract: A method for purifying a gaseous hydride, which comprises bringing a crude gaseous hydride into contact with at least one material from nickel arsenides, nickel phosphides, nickel silicides, nickel selenides, or nickel borides to remove oxygen contained in the crude gaseous hydride.

Abstract: A process for forming polysilanes from silicon hydrides by contacting the silicon hydride with catalytic amounts of selected scandium, yttrium and rare earth metal hydrides, and a process for hydrosilation of alpha-olefins in which an alpha-olefin is contacted with a silicon hydride in the presence of catalytic amounts of selected scandium, yttrium and rare earth metal compounds.

Abstract: There is here provided a method for manufacturing silane by subjecting a raw material, trialkoxysilane, to a disproportionation reaction in the gaseous phase in the presence of a catalyst which is an oxide of a metal in the third period of the periodic table. According to the present invention, silane can be obtained effectively without any by-products, and the reaction can be easily controlled and stopped promptly in an emergency.

Abstract: A process for the production of disilane from monosilane, in which a gaseous mixture of monosilane and hydrogen is subjected to a plasma discharge.

Abstract: A method is disclosed for separating gaseous silicon compounds from hydrogen and/or hydracids. Specifically, the method comprises the utilization of semi-permeable membranes for such gaseous separation. Particularly preferred is a composite membrane comprised of a coating separation layer of sulfonated polysulfone and a support layer of polysulfone. Mixtures of hydrogen and silane are particularly suitable for being separated by means of composite membrane separation.

Abstract: A process is provided wherein tertiary ammonium trichlorosilyl, a complexing tertiary amine, and an alkali metal aluminum tetrahydride are reacted together in molar proportion of about 1:2:3, such that silane and tertiary amine alane are produced. Tertiary ammonium trichlorosilyl may be pre-formed or formed in situ by the reaction of trichlorosilane and tertiary amine. Yields are dramatically higher when the process is conducted in the presence of a tris(polyalkoxyalkyl)amine phase transfer catalyst.A sequential process is also provided for the preparation of silane and aluminum trifluoride. In the first part of this sequence, silane and tertiary amine alane are produced as described above. In the second part of the sequence, silicon tetrafluoride is reacted with the amine alane, producing additional silane and aluminum trifluoride.

Abstract: A process for producing monosilane, which comprises disproportionating an alkoxysilane of the formula:H.sub.n Si(OR).sub.4-n (I)wherein R is an alkyl group having from 1 to 6 carbon atoms or a cycloalkyl group and n is an integer of 1, 2 or 3, in the presence of a catalyst, wherein the catalyst comprises at least one compound selected from the group consisting of aromatic alkoxides of the formula:MOAr (II)wherein M is a metal of Group Ia of the Periodic Table and Ar is a substituted or unsubstituted aromatic hydrocarbon group, and quaternary ammonium and phosphonium compounds of the formula:R.sup.1 R.sup.2 R.sup.3 R.sup.4 ZX (III)wherein each of R.sup.1, R.sup.2, R.sup.3 and R.sup.4 which may be the same or different, is a substituted or unsubstituted alkyl or aryl group, Z is a nitrogen atom or a phosphorus atom and X is an anion.

Abstract: A process is described by which two useful products, silane and hydrocarbyloxyaluminun hydride, can be produced concurrently and in excellent yield. The process involves reaction between tetrahydrocarbyloxysilane such as Si(OEt).sub.4 and tertiary amine alane such as AlH.sub.3 .multidot.NEt.sub.3.

Abstract: A continuous method for preparing silane and a co-product by reacting a metal hydride such as NaAlH.sub.4 with a silicon halide such as SiF.sub.4. The method involves a reactor loop comprising a primary reactor, a secondary reactor and a separation zone. Most of the metal hydride is reacted in the first reactor to which it is added in a substantially constant rate. The remainder of the hydride is reacted in the secondary reactor, in which all or substantially all of the silicon halide is added. The rate of silicon halide addition is governed by feed back from the reaction in the secondary reactor, (.rarw.T so that stoichiometric or substantially stoichiometric operation is achieved. This conserves resources, provides improved co-product and reduces costs.

Abstract: There is here disclosed a ladder polysilane represented by the general formula (I): ##STR1## wherein n is a positive integer, and R is a halogen atom, a hydrogen atom, a hydroxyl group, an alkyl group, an alkenyl group, an aryl group or an alkoxy group having 20 or less carbon atoms, and the alkyl, alkenyl, aryl or alkoxy group may contain a functional group such as --COOH, --SO.sub.3 H, --NH.sub.2, --NO.sub.2, --NCO, --F, --Cl, --BR, --I or --OH. In addition, a method for preparing the aforesaid ladder polysilane is also disclosed here.

Abstract: Trichlorosilane, SiHCl.sub.3, is facilely prepared by (i) thermally reducing silicon tetrachloride, SiCl.sub.4, with hydrogen to produce reaction admixture comprising SiHCl.sub.3 and hydrochloric acid, said thermal reduction being carried out in a thermal plasma while tempering the reaction medium with a cooling gas, (ii) reacting said step (i) reaction admixture with elemental silicon at a temperature of from about 250.degree. to 350.degree. C. to produce SiHCl.sub.3 and hydrogen therefrom, and thence (iii) separating (iiia) the plasma-creating, hydrogen and cooling gases, and (iiib) product silicon chlorides therefrom.

Abstract: The invention relates to the selective and stepwise reduction of polyhalosilanes by reacting at room temperature or below with alkyltin hydrides without the use of free radical intermediates. Alkyltin hydrides selectively and stepwise reduce the Si--Br, Si--Cl, or Si--I bonds while leaving intact any Si--F bonds. When two or more different halogens are present on the polyhalosilane, the halogen with the highest atomic weight is preferentially reduced.

Abstract: There is disclosed a process for producing silanes by reducing polyhalosilane with a mixture of alkyl aluminum hydride and trialkyl aluminum, in which a treatment for reducing the content of trialkyl aluminum in the mixture is lowered to 10 mol. % or less of alkyl aluminum hydride prior to the reduction reaction.As to methods for reducing the content of trialkyl aluminum in the mixture, there are provided, for example, distillation, recrystallization, separation by complex formation, pyrolysis of trialkyl aluminum and decomposition by hydrogenation of trialkyl aluminum.

Abstract: A process for producing silanes represented by the general formula SI.sub.n H.sub.2n+2 wherein n is 1 or 2, which comprises (a) preparing a silicon-magnesium alloy containing at least one element selected from the goup consisting of Li, Na, K, Ca, Ba, Ti, Zr, Nb, Cr, Mo, Mn, Fe, Co, Ni, Pd, Cu, Ag, Zn, Cd, Al, Sn, Pb, Bi, Se, S and C as a third component element; (b) reacting the alloy containing the third component element with an acid in an ammonia solvent; and (c) thus, varying the ratio of Si.sub.2 H.sub.6 formed to SiH.sub.4 formed.

Abstract: Silicon halides and silicon hydrohalides, such as SiCl.sub.4, SiBr.sub.4, and SiHCl.sub.3 react with alkali metal aluminum hydrides such as NaAlH.sub.4 and LiAlH.sub.4 in the presence of a hydrocarbon reaction medium; e.g., toluene, and a tetraalkyl ammonium salt, and in the substantial absence of an ether, to produce silane and a metal aluminum halide co-product which is not tightly complexed to an organic substance.

Abstract: Process for the preparation of silane and a tertiary amine alane, said process comprising reacting:(a) an alkali metal aluminum tetrahydride having the formula MAlH.sub.4, wherein M is an alkali metal selected from the class consisting of lithium, sodium and potassium,(b) silicon tetrachloride, and(c) a complexing tertiary amine, such that the molar proportion of (a) to (b) to (c) is about 4:1:4.In this process, NaAlH.sub.4 and triethylamine are preferred reactants. The amine alane product can be reacted with additional silicon halide to prepare additional silane. This step can be conducted utilizing amine alane in the reaction mixture produced by the process above, and is preferably conducted using SiF.sub.4 as the silicon tetrahalide to produce AlF.sub.3 as a co-product. Both AlF.sub.3 and silane are valuable articles of commerce.

Abstract: Silanes are produced by the disproportionation and/or redistribution reaction of chlorosilanes using a novel catalyst having a longer life and consisting of a quaternary phosphonium salt bonded to an organic macromolecule or polymer, represented by the following general formula: ##STR1## wherein .circle.P is an organic macromolecule or polymer, A is a bridging group between phosphorus and the organic macromolecule or polymer, R.sup.1, R.sup.2 and R.sup.3 are selected from the group consisting of hydrogen, C.sub.1 -C.sub.20 alkyl groups and aralkyl groups such as benzyl and phenethyl groups, which can contain oxygen or halogen atoms, and X is a halogen atom.

Abstract: A process for producing silane by reacting a silicon halide with highly reactive magnesium and a cyclic process for producing silane by reacting magnesium hydride with a silicon halide, reacting the magnesium halide as formed with an alkali metal to recover elemental magnesium, and pressure hydrogenating said magnesium to form magnesium hydride and repeat the cycle. A highly reactive magnesium hydride is formed by the homogeneously catalyzed pressure hydrogenation of magnesium, preferably using an activated transition metal catalyst such as TiCl.sub.4 and a polycyclic organic compound such as anthracene. The highly activated magnesium hydride is thereafter used for reaction with silicon halide to produce silane.