Abstract: The present invention relates to a process for producing a hydrophobized silica aerogel, comprising the following steps: a) preparing a hydrophobized silica gel comprising alkoxy groups; b) drying of the hydrophobized silica gel obtained in step a); c) treatment of the product obtained in step b) with a gas mixture comprising water and a base or an acid. A hydrophobized silica aerogel with a reduced alkoxy group content, suitable for thermal insulation applications, is also provided.

Abstract: Amorphous silicon carbon composite particles contain, as components of the particles, 85 to 99.63 wt.-% silicon content, 0.3 to 15 wt.-% carbon content, and at least 0.07 wt.-% hydrogen content, where the components sum up to 100 wt.-%. The carbon content in the area beneath the surface of the particles, starting from the surface and reaching up to at least 30 nm from the surface in a direction to the centre of the particles, is at least 3 wt.-% higher than in the area of the centre of the particles. The area of the centre is the remaining part of the particles and is directly joined to the area beneath the surface.

Abstract: Novel epoxy-functional alkoxysilanes have, for example, formulae II, III, IV, V, and VI.

Abstract: Novel epoxy-functional alkoxysilanes have, for example, formulae II, III, IV, V, and VI.

Abstract: A process can prepare a 3-glycidyloxypropylalkoxysilane of formula (I), (R?)O—(CH2)3—Si(OR)3 (I), where R groups are independently a methyl or ethyl group and R? represents an H2C(O)CHCH2— group. The process includes reacting (i) a functionalized alkene of formula (II), (R?)O—C3H5 (II), where R? represents an H2C(O)CHCH2— group, with (ii) at least one hydroalkoxysilane of formula (III), HSi(OR)3 (III), where R groups are independently a methyl or ethyl group. The reacting takes place in the presence of (iii) a Karstedt catalyst or a catalyst having hexachloroplatinic acid as a homogeneous catalyst, and (iv) 2-ethylhexanoic acid, isononanoic acid, or both. The process further includes obtaining a product of the reacting.

Abstract: A process can prepare a 3-glycidyloxypropylalkoxysilane of formula (I), (R?)O—(CH2)3—Si(OR)3 (I), where R groups are independently a methyl or ethyl group and R? represents an H2C(O)CHCH2— group. The process includes reacting (i) a functionalized alkene of formula (II), (R?)O—C3H5 (II), where R? represents an H2C(O)CHCH2— group, with (ii) at least one hydroalkoxysilane of formula (III), HSi(OR)3 (III), where R groups are independently a methyl or ethyl group. The reacting takes place in the presence of (iii) a Karstedt catalyst or a catalyst having hexachloroplatinic acid as a homogeneous catalyst, and (iv) 2-ethylhexanoic acid, isononanoic acid, or both. The process further includes obtaining a product of the reacting.

Abstract: Described is a method for producing alkenyl halosilanes by reacting alkenyl halide selected from the group comprising vinyl halide, vinylidene halide, and allyl halide with halosilane selected from the group comprising monohalosilane, dihalosilane, and trihalosilane in the gas phase in a reactor comprising a reaction tube (1) that has an inlet (2) at one end and an outlet (3) at the other end, said reactor further comprising an annular-gap nozzle (4) that is mounted on the inlet (2), extends into the reaction tube (1), and has a central supply duct (5) for one reactant (7) and a supply duct (6), which surrounds the central supply duct (5), for the other reactant (8). In order to carry out said method, alkenyl halide is injected into the reaction tube (1) through the central supply duct (5), halosilane is injected thereinto through the surrounding supply duct (6), and both substances flow through the reaction tube (1) in the direction of the outlet (3).

Abstract: What is described is a process for continuously esterifying halosilanes of the formula I with alcohols of the formula II to give silane esters of the formula III in a single column (1) R1aSiHalb??(I) R2—(OH)??(II) R1aS—(OR2)b??(III) in which R1 is hydrogen or a monovalent organic radical, where any two R1 radicals within a molecule may be different within the scope of the given definitions, Hal is a halogen atom, a plurality of Hal atoms within a molecule may be different within the scope of the given definitions, R2 is a monovalent organic radical, a and b are integers from 0 to 4 and the sum total of a and b is 4, comprising the measures of: i) feeding the total amount of the halosilane of the formula I required for the reaction in liquid form through line (6) into the upper third of the column (1), ii) feeding at least 60% by weight of the alcohol of the formula II required for the reaction in liquid form through line (7) into the upper third of the column (1), iii) feeding the remainder of the a

Abstract: A process for preparing alkenylhalosilanes by reacting alkenyl halide in the gas phase in a reactor comprising a reaction tube (1) equipped with an inlet (2) at one end of the tube and with an outlet (3) at the other end of the tube, and having a gas inlet device (4) having a plurality of gas feed points (5) that are spaced apart in the direction of the longitudinal axis of the reaction tube (1) and open into the reaction tube (1). The process permits the preparation of alkenylhalosilanes in high yield and with high selectivity. The formation of soot is distinctly lower compared to conventional reactors.

Abstract: What is described is a process for continuously esterifying halosilanes of the formula I with alcohols of the formula II to give silane esters of the formula III in a single column (1) R1aSiHalb ??(I) R2—(OH) ??(II) R1aS—(OR2)b ??(III) in which R1 is hydrogen or a monovalent organic radical, where any two R1 radicals within a molecule may be different within the scope of the given definitions, Hal is a halogen atom, a plurality of Hal atoms within a molecule may be different within the scope of the given definitions, R2 is a monovalent organic radical, a and b are integers from 0 to 4 and the sum total of a and b is 4, comprising the measures of: i) feeding the total amount of the halosilane of the formula I required for the reaction in liquid form through line (6) into the upper third of the column (1), ii) feeding at least 60% by weight of the alcohol of the formula II required for the reaction in liquid form through line (7) into the upper third of the column (1), iii) feeding the remainder

Abstract: Described is a method for producing alkenyl halosilanes by reacting alkenyl halide selected from the group comprising vinyl halide, vinylidene halide, and allyl halide with halosilane selected from the group comprising monohalosilane, dihalosilane, and trihalosilane in the gas phase in a reactor comprising a reaction tube (1) that has an inlet (2) at one end and an outlet (3) at the other end, said reactor further comprising an annular-gap nozzle (4) that is mounted on the inlet (2), extends into the reaction tube (1), and has a central supply duct (5) for one reactant (7) and a supply duct (6), which surrounds the central supply duct (5), for the other reactant (8). In order to carry out said method, alkenyl halide is injected into the reaction tube (1) through the central supply duct (5), halosilane is injected thereinto through the surrounding supply duct (6), and both substances flow through the reaction tube (1) in the direction of the outlet (3).

Abstract: What is described is a process for preparing alkenylhalosilanes by reacting alkenyl halide selected from the group of vinyl halide, vinylidene halide and allyl halide with halosilane selected from the group of mono-, di- and trihalosilane in the gas phase in a reactor comprising a reaction tube (1) equipped with an inlet (2) at one end of the tube and with an outlet (3) at the other end of the tube, and having a gas inlet device (4) having a plurality of gas feed points (5) which are spaced apart in the direction of the longitudinal axis of the reaction tube (1) and open into the reaction tube (1). To perform the process, mono-, di- or trihalosilane is passed through the inlet (2) into the reaction tube (1) and flows through the reaction tube (1) in the direction of outlet (3), and vinyl halide, vinylidene halide or allyl halide flows through the gas feed points (5) in sections into the gas stream in the interior of the reaction tube (1).

Abstract: The present invention relates to a process for preparing glycidyloxy-alkylalkoxysilanes of the general formula (I) (R?)O—CnH2nSi(R?)m(OR)3-m(I) in which R and R? groups are each independently linear or branched alkyl groups having from 1 to 4 carbon atoms, n is 1, 2, 3, 4, 5, 6, 7 or 8 and m is 0, 1, 2 or 3, and R? is an H2C(O)CH— or H2C(O)CHCH2— group, by reacting (i) a functionalized alkene of the general formula (II) (R?)O—CnH2n-1(II) in which R? is an H2C(O)CH— or H2C(O)CHCH2— group and n is 1, 2, 3, 4, 5, 6, 7 or 8 with (ii) at least one hydroalkoxy-silane of the general formula (III) HSi(R?)m(OR)3-m (III) in which R and R? groups are each independently linear or branched alkyl groups having from 1 to 4 carbon atoms and m is 0, 1, 2 or 3, in the presence (iii) of at least one homogeneous catalyst, (iv) of at least one solvent and/or of a diluent and (v) of at least one promoter.

Abstract: The present invention relates to a process for preparing glycidyloxy-alkylalkoxysilanes of the general formula (I) (R?)O—CnH2nSi(R?)m(OR)3-m (I) in which R and R? groups are each independently linear or branched alkyl groups having from 1 to 4 carbon atoms, n is 1, 2, 3, 4, 5, 6, 7 or 8 and m is 0, 1, 2 or 3, and R? is an H2C(O)CH— or H2C(O)CHCH2— group, by reacting (i) a functionalized alkene of the general formula (II) (R?)O—CnH2n-1(II) in which R? is an H2C(O)CH— or H2C(O)CHCH2— group and n is 1, 2, 3, 4, 5, 6, 7 or 8 with (ii) at least one hydroalkoxy-silane of the general formula (III) HSi(R?)m(OR)3-m (III) in which R and R? groups are each independently linear or branched alkyl groups having from 1 to 4 carbon atoms and m is 0, 1, 2 or 3, in the presence (iii) of at least one homogeneous catalyst, (iv) of at least one solvent and/or of a diluent and (v) of at least one promoter.

Abstract: A process for preparing epoxysilanes by reacting a hydrogensilane with an allyl glycidyl ether in the presence of a catalyst and working up the crude product obtained, where the catalyst is removed from the crude product and the crude product is subsequently distilled.

Abstract: The invention relates to a process for preparing vinyl chlorosilanes, that includes thermally and non-catalytically reacting chlorosilane with vinyl chloride at a temperature of 550 to 700° C. by flowing the chlorosilane and vinyl chloride through a ring-gap space in a ring-gap reactor to produce a reaction gas; the ring-gap space having a cross-sectional area and a volume; and, after the flowing, further reacting, adiabatically, the reaction gas in a second zone to produce a hot reaction gas that contains vinylchiorosilane; wherein the second zone has a cross-sectional area that is greater than the cross-sectional area of the ring-gap space; and wherein the second zone has a volume that is in a ratio to the volume of the ring-gap space of 0.15:1 to 1.5:1. The invention also provides an apparatus for carrying out the above process.

Abstract: A process for the continuous preparation of 3-halopropylorganosilanes of the general structure RbH3-a-bXaSiCH2CH2CH2Y  (III), where: R is CH3, C2H5, C3H7, OCH3, OC2H5 or OC3H7, X is F, Cl, Br or I, Y is F, Cl, Br or I, and a and b are each one of the numbers 0, 1, 2 or 3 and the sum a+b is 1, 2 or 3, comprising reacting, as starting materials, an allyl halide with a silane carrying at least one H atom, wherein the starting materials are present in stoichiometric amounts or one of the starting materials is present in substoichiometric amounts, wherein the reaction carried out is a partial reaction of from 10% to 80%, on a molar basis, of the starting materials, based on either material, when both are present in stoichiometric amounts, or based on the substoichiometric material.

Abstract: The invention relates to a process for preparing vinylchlorosilanes by thermal non-catalyzed reaction of chlorosilanes with vinyl chloride at from 550 to 700° C., using a ring-gap reactor which includes rapidly cooling the hot reaction gases after they have flowed through the ring-gap space, by quenching them with a liquid.

Abstract: A process for preparing alkoxysilanes by reacting alcohols with halosilanes which are dissolved in a nonpolar solvent that is immiscible with the alcohol.

Abstract: The invention relates to a process for preparing 3-glycidyloxypropyltrialkoxysilanes of the general formulaCH.sub.2 (O)CHCH.sub.2 --O--(CH.sub.2).sub.3 Si(OR).sub.3 (I),in which R is an alkyl radical, by reacting allyl glycidyl etherCH.sub.2 (O)CHCH.sub.2 --O--CH.sub.2 CH.dbd.CH.sub.2 (II),with a trialkoxysilane of the general formulaHSi(OR).sub.3 (III),in which R is again an alkyl radical, in a heterogeneous, platinum-catalyzed hydrosilylation reaction, where the catalyst employed is a platinum(0) catalyst on a nonmetallic support.