Abstract: Preforms are produced from ceramic and/or metallic fibers by injection molding or extruding a mixture containing the fibers and a thermoplastic binder, said thermoplastic binder being polyoxymethylene, which after the shaping is removed by treatment in a gaseous acid-containing atmosphere or in a gaseous BF.sub.3 -containing atmosphere.

Abstract: Thermoplastic materials for the production of ceramic moldings containA) 40-65% by volume of a sinterable inorganic non-metallic powder,B) 35-60% by volume of a mixture ofB1) 70-90% by weight of a polyoxymethylene homo- or copolymer having up to 10 mol % of comonomer units andB2) 10-30% by weight of a polyoxymethylene copolymer with a comonomer content of 20-99 mol %, poly-1,3-dioxolane, poly-1,3-dioxane or poly-1,3-dioxepan, or of a polymer which is homogeneously dissolved or is dispersed with a mean particle size of less than 1 .mu.m in B1) or a mixture thereof,as a binder, andC) 0-5% by volume of a dispersant.

Abstract: Thermoplastic materials containing ceramic powders as fillers are prepared by introducing the thermoplastics into a mixing zone comprising a plurality of zones. The thermoplastics are melted in a first zone. In the subsequent second zone, the molten plastic is mixed with a suspension of a ceramic powder in an organic solvent, and the solvent is removed by distillation under reduced pressure in the third zone. In the fourth zone, the melt containing the ceramic powder is compressed and extruded. The process is suitable for the preparation of thermoplastic materials having a degree of filling of from 40 to 80% by volume of ceramic powders.

Abstract: A thermoplastic composition containing a ceramic powder per volume fill level of from 40 to 80% together with an oxidic sinter additive is prepared by melting the thermoplastic in a first zone of a mixing section consisting of a plurality of zones, admixing the molten plastic in the adjoining second zone with a suspension of a ceramic powder in an organic solvent which contains a hydrolyzable precursor compound of the oxidic sinter additive in solution, hydrolyzing the precursor compound in the third zone by adding water, removing the solvent and any volatile hydrolysis products by distillation under reduced pressure in the fourth zone, and compressing and extruding the melt containing the ceramic powder from the fifth zone.

Abstract: Polymers contain, as mesogenic groups, groups which produce a discotic phase, and furthermore can control pleochroic dyes.The novel polymers possess novel properties, and combination of properties, which the conventional polymers which form liquid-crystalline phases do not possess.The polymers can be used in electro-optical displays, in storage elements, as electrically or photo-electrically conductive polymers and as strain sensors.

Abstract: A membrane of an organic polymer, which contains a crystalline carrier compound capable of selective transport of low molecular weight substances, and the preparation and use of the said membrane.

Abstract: In the preparation of compact, crystalline and pore-free moldings from an oxide ceramic, amorphous oxide powders of beryllium, magnesium, aluminum, boron, zirconium, thorium or silicon or mixed oxides of silicon with these elements, in which some of the oxygen is replaced by bound nitrogen, are used as starting materials. These amorphous oxide powders containing bound nitrogen are compressed in a first stage at above the glass transition temperature but below the crystallization temperature to give a glassy molding, and the latter is then heated in a second stage to above the crystallization temperature. In the case of the individual oxides, from 5 to 30% of the oxygen are replaced by bound nitrogen, and in the case of the mixed oxides of silicon with these elements from 50 to 90% of the oxygen are replaced by bound nitrogen.

Abstract: Ceramic moldings, in particular those having geometrically complicated shapes, are produced by a process in which a ceramic powder is mixed with a molding additive and the mixture is injected into a mold. In order to improve the mechanical properties of the molding, a solution of a high molecular weight polymer in a solvent is used as the molding additive. The mixture is injected at a temperature below the boiling point of the solvent and under from 100 to 1,500 bar into a porous, gas-permeable mold which is at a temperature above the boiling point of the solvent, the injection pressure being maintained until gas no longer escapes from the molding material or the mold.

Abstract: A plastics mixture which absorbs electromagnetic radiation consists of a heat-stable thermoplastic polymer and from 1 to 90% by weight of a ferrite, titanate or zirconate having a particle size of from 100 to 5,000 .ANG.. The mixture is prepared by combining the metal components in the form of organometallic compounds, mixing them with the thermoplastic, adding the amount of water required for hydrolysis and heating the mixture to about 250.degree. C.

Abstract: Polymers contain, as mesogenic groups, groups which produce a discotic phase, and furthermore can contain pleochroic dyes.The novel polymers possess novel properties, and combinations of properties, which the conventional polymers which form liquid-crystalline phases do not possess.The polymers can be used in electro-optical displays, in storage elements, as electrically or photo-electrically conductive polymers and as strain sensors.

Abstract: In amorphous silicon nitride powder, from 0.5 to 40 mol % of the silicon are replaced by one or more of the elements boron, aluminum, yttrium, lanthanum, titanium, zirconium, tungsten and molybdenum.The powder is obtained by reacting the halides of the corresponding elements, which are dissolved in an inert organic solvent in the particular ratio desired, with ammonia. The solid reaction product formed is separated off from the liquid phase and treated at from 800.degree. to 100.degree. C.The powder is particularly suitable as a starting material for the production of sintered articles.

Abstract: Compact pore-free silicon carbide moldings are produced by compressing amorphous silicon carbide powder in the absence of sintering assistants at from 1400.degree. to 1800.degree. C. and under from 100 to 2000 kp/cm .sup.2 to give dense, glassy moldings. In a subsequent stage the resulting glassy moldings are converted into crystalline .alpha.-silicon carbide at from 1950.degree. to 2200.degree. C.

Abstract: Methanol/air fuel cells consisting of(A) a cathode,(B) an anode and(C) A CO.sub.2 -permeable anion exchanger membrane as the electrolyte.

Abstract: Composites of heat-stable thermoplastic polymers and silica reinforcing fibers having diameters of less than 1000 nm are prepared by polycondensation of silicic acid or polysilicic acid in the melt or solution of the thermoplastic under the influence of a high shear gradient. The silicic acids or polysilicic acids are salted out from aqueous solution in order to transfer then to an organic solvent, which is also a solvent for the thermoplastic.

Abstract: In microelectronic components and thick-film hybrid circuits, the multilayer substrates of the said components and the substrates of the said circuits are produced using liquid crystalline polymers which can be processed by a thermoplastic method.

Abstract: Wholly aromatic mesomorphic polyesters which form a liquid-crystalline fiber-forming melt below 320.degree. C. and are composed of(a) not less than 10 mol % of repeat units of the formula I ##STR1## (b) a molar amount equivalent to the total amount of components (c) and (d) of repeat units of the formula II ##STR2## (c) from 3 to 20 mol % of repeat units of the formulae III and/or IV ##STR3## and (d) from 5 to 30 mol % of repeat units of the formula V ##STR4## the molar proportions of components a, b, c and d adding up to 100 mol % in each case, the preparation thereof and moldings and coatings prepared therefrom.

Abstract: A battery is composed of methanol/air fuel cells which in turn are composed of an anode (1), a cathode (2) and a CO.sub.2 -permeable anion exchanger membrane (3) as electrolyte, wherein anode (1) and cathode (2) are present on a common current offlead which is configured as a truncated cone having a small apex angle and internal stepping and wherein a plurality of these offleads are stacked in one another on a feed tube (6) to form a battery.

Abstract: In a battery composed of methanol/air fuel cells which in turn are composed of a cathode, an anode and a CO.sub.2 -permeable anion exchanger membrane as electrolyte, a plurality of cathodes and anodes are in a parallel arrangement in a common cathode compartment and anode compartment respectively.

Abstract: Composite materials consisting of heat-resistant thermoplastic polymers and metal oxide reinforcing fibers having diameters of less than 1000 nm are prepared by hydrolyzing an organometallic compound, preferably an aluminum alkoxide, in a melt or solution of the thermoplastic under the action of a high shear gradient.

Abstract: Pore-free, compact moldings of silicon nitride are produced by a method in which amorphous silicon nitride powder is compressed in a first stage at from 1200.degree. to 1350.degree. C. and from 50 to 600 kp/cm.sup.2 to give a glassy molding, and the silicon nitride is converted in a second stage to crystalline silicon nitride at from 1400.degree. to 1800.degree. C. without the use of pressure.