Abstract: Crosslinkable compositions based on organosilicon compounds and moldings produced therefrom further contain glass flakes having a thickness of from 0.1 to 20 &mgr;m, a length of from 1 to 5000 &mgr;m and a width of from 1 to 5000 &mgr;m, and a width or length to thickness ratio in the range from 10:1 to 2000:1. The compositions, when cured, exhibit excellent tear resistance, have surfaces exhibiting a low coefficient of friction, and a relatively low calorific value.

Abstract: Storage stable multiple emulsions of a polar phase A1, a nonpolar phase B and a polar phase A2, or of a nonpolar phase B1, a polar phase A and a nonpolar phase B2, employ particulate solids smaller than 1 &mgr;m to stabilize the resulting A1/B/A2 or B1/A/B2 multiple emulsions against coalescence, with the proviso that surface-active substances are present only up to a maximum concentration of less than 0.1 times the critical micelle concentration of the surface-active substances in phase A, A1, A2. The multiple emulsions have numerous uses including controlled release of active substances from a dispersed phase.

Abstract: The invention provides a process for preparing adhesives having improved adhesion, in the form of their aqueous dispersions or water-redispersible dispersion powders, by emulsion polymerization in the presence of polyvinyl alcohol with or without drying of the dispersion obtainable by this process, which comprises polymerizing a comonomer mixture comprising a) one or more monomers from the group consisting of the vinyl esters of unbranched and branched carboxylic acids of 1 to 10 carbon atoms, the esters of acrylic acid and methacrylic acid with branched and unbranched alcohols of 1 to 12 carbon atoms, vinylaromatic compounds, vinyl halides and alpha-olefins, and b) from 0.01 to 50% by weight, based on the overall weight of the comonomers, of a vinyl ester of alpha-branched tertiary monocarboxylic acids of 11 carbon atoms, in the presence of c) from 0.1 to 15% by weight, based on the overall weight of the comonomers, of polyvinyl alcohol.

Abstract: Antifoam formulations contain a siloxane antifoam and a polyether/polysiloxane copolymer of the general formula (R2R*SiO)2(RR′SiO)x(R2SiO)y(RR″SiO)2  (I) wherein R* is either R, R′, or R″, and wherein R′ is R1O—(CH2CH2O)a[CH2CH(CH3)O]b[CH2CH(CH2CH3)O]c—R2—  (R′) and wherein R″ is —R2—O—(CH2CH2O)d[CH2CH(CH3)O]e[CH2CH(CH2CH3)O]f—R2—  (R″) wherein R, R1, R2, a, b, c, d, e, f, x, y, and z are defined herein.

Abstract: A wire saw and method for cutting wafers from a workpiece, in which a saw wire is guided multiple times around wire-guiding rolls. The wire-guiding rolls have a rotatable bearing arrangement and two adjacent wire-guiding rolls delimit a saw gate. The saw has ceramic sliding-contact bearings for rotatably bearing the wire-guiding rolls.

Abstract: A process for separating metal chlorides from a suspension of metal chlorides in chlorosilanes, in which the suspension is filtered under pressure in the absence of air and moisture forming a filter cake, which is granulated and passed to a dissolution zone where the metal chlorides are dissolved to form an aqueous metal chloride solution. The invention also relates to a filtration and dissolution apparatus for this process, and to an apparatus for introducing the crude reaction gas into a circulated suspension of metal chlorides in chlorosilanes, thus producing a feedstock for the process.

Abstract: Antimisting additives are used in crosslinkable silicone coating compositions for reducing aerosol formation, the antimisting additives being alkenyl-functional siloxane copolymers prepared by reacting a hydrocarbon containing at least three aliphatic double bonds, and with an organosiloxane (2) having terminal Si-bonded hydrogen atoms in the presence of a hydrosilylation catalyst (3) at a ratio of Si-bonded hydrogen to aliphatic double bonds of from 1.3 to 10, and subsequently reacting the resulting SiH-containing hydrocarbon-siloxane copolymer with an &agr;,&ohgr;-dialkenylsiloxane polymer (4) in the presence of a hydrosilylation catalyst (3) at a ratio of aliphatic double bonds to Si-bonded hydrogen of from 1.2 to 10, and optionally, in another step, equilibrating the resulting alkenyl-functional siloxane copolymers with an organopolysiloxane (5).

Abstract: A method is provided for producing protective colloid-stabilized vinyl aromatic-1.3-diene-copolymers in the form of their aqueous polymer dispersions or in the form of a powder which can be re-dispersed in water, by emulsion-polymerizing a mixture containing at least one vinyl aromatic and at least one 1,3-diene in the presence of a protective colloid and optionally, drying the resulting polymer dispersions. In the method part of the protective colloid is provided straightaway and part is metered.

Abstract: An immobilizing structure for use in immobilizing a ceramic monolith in a catalytic converter employs a molding which comprises finely divided metal oxide and fibers which do not represent a health risk, has a density of 100-240 kg/m3, and has a compression to at least 96% of its original thickness at a pressure of 1 bar applied for a period of 5 minutes, and exhibits a recovery of this compression to more than 70% of its initial value within about one minute after removal of the pressure.

Abstract: Crosslinkable organopolysiloxane compositions, comprising;

Abstract: A process for producing an SiO2 shaped body which is vitrified in a partial region or completely, in which process an amorphous, porous SiO2 preform is sintered or vitrified by contactless heating by means of laser radiation, by means of which contamination of the SiO2 shaped body with foreign atoms is avoided.

Abstract: The invention relates to thickeners based on fully or partially hydrolyzed vinyl alcohol copolymers with a molecular weight Mw greater than 100,000, obtainable by hydrolyzing vinyl acetate copolymers which, besides vinyl acetate units, also contain comonomer units which derive from one or more comonomers selected from the group consisting of 1-(C1-5)-alkylvinyl esters of C1-5 carboxylic acids, allyl esters, vinyl esters of alpha-branched C5-12 carboxylic acids, and C1-18-alkyl (meth)acrylates, in the form of their aqueous solution or in powder form.

Abstract: Silylated silica is prepared by silylating silica with an organosiloxane composed of A units of the formula (I)

Abstract: Surface-modified solids bearing groups of the formula I

Abstract: The invention relates to a security marking whose level of proof against forgery is increased relative to known security markings, comprising liquid-crystalline material with chiral phase, wherein present within the security marking are at least two liquid-crystalline materials with chiral phase which differ in at least one property selected from the group consisting of handedness, color and color flop and which are arranged in the form of a structured or unstructured marking or a multilayer marking or in the form of liquid-crystalline pigments in a liquid-crystalline matrix, or wherein there is at least one liquid-crystalline material with chiral phase whose reflection band has been broadened by means of special techniques, or wherein there is at least one liquid-crystalline material with chiral phase which has a defined three-dimensional arrangement.

Abstract: The invention provides a polymer composition for flexibilizing building materials, in the form of their aqueous dispersion or of powder redispersible in water, containing a) at least one water-insoluble, film-forming polymer of one or more ethylenically unsaturated monomers capable of free radical polymerization, b) at least one compound from the group consisting of the water-soluble polymers of one or more ethylenically unsaturated monomers capable of free radical polymerization, and the ionic and nonionic emulsifiers, and c) a mixture of at least two organosilicon compounds, at least one of which is an amino-functional organosilicon compound present in salt form.

Abstract: The vinyl aromatic-1,3-diene copolymers stabilized with protection colloids are used in the form of aqueous polymer dispersions or water-redispersible polymer powders for modifying materials that contain plaster or calcium carbonate. The polymer dispersions or polymer powders are obtained by the emulsion-polymerization of a mixture containing at least one vinyl aromatic and at least one 1,3-diene in the presence of at least one protection colloid and without any emulsifier, and by optionally drying the aqueous polymer dispersions thus obtained.

Abstract: Compositions prepared by mixing (A) 50-90 wt % of organopolysiloxane having a viscosity of from 50 to 100·106 mm2/s at 25° C., (B) 10-50 wt % of a metal oxide from the group consisting of titanium oxide, zirconium dioxide, zinc oxide, cerium(III) and cerium(IV) oxide, (C) 0.3-5 wt % of organosilicon compound containing basic nitrogen bound to silicon via carbon, (D) 0.05-0.5 wt % of platinum calculated as the element, in the form of a bis(alkynyl)platinum complex which additionally includes donor ligands, and (E) from 0 to 5 wt %, preferably 0 wt %, of further components, the sum of the percentages chosen within each of the ranges specified under (A) to (E) being 100 wt %, and the wt % in each case being based on the total weight of the additive, are highly suitable as additives to crosslinkable organosilicon compositions, providing one or more of improved tracking resistance, high arc resistance, and decreased flammability.

Abstract: The invention relates to a process for the chlorination of methylsilanes, which comprises reacting methylsilanes with chlorine in the presence of at least 0.1% by weight of hydrogen chloride, based on the weight of methylsilane of the formula (II), under the action of electromagnetic radiation which induces chlorination, chlorine being used in a substoichiometric amount based on the methylsilane of the formula (II), and the reaction being carried out at temperatures below the boiling point of the methylsilane of the formula (II). The invention further relates to an apparatus suitable for carrying out the chlorination of an industrial scale.

Abstract: A water-soluble, crosslinkable protective colloid is provided having a molecular weight of least than 500,000 comprising: a) 20 to 959 by weight of monomer units containing sulphonic acid or sulphonate groups, b) 4 to 800 by weight of monomer units containing N-methylol or N-alkoxymethyl groups, and c) 0.1 to 20% by weight of hydrophobic monomer units such as water insoluble ethylenically unsaturated compounds and the hydrophobic end groups of initiator radicals or regulator molecules. Optionally, up to 50% by weight of the monomer units containing sulphonic acid or sulphonate groups can be replaced by monomer units containing carboxyl groups or monomer units containing amide groups.