Abstract: The invention essentially relates to the use of ceramic powders whose surface has been rendered hydrophobic to produce fine-particle dispersions having a high solids content and a low viscosity. The invention further relates to specific ceramic powders whose surface has been rendered hydrophobic, and methods of producing them. Ceramic powders whose oxidic surface has hydroxide groups possessing a basic or amphoteric character can be rendered hydrophobic, for example, through the effect of a hydrophobic carboxylic acid. Acidic oxides are rendered hydrophobic through treatment with metal-containing hydrophobing agents which are, however, also suitable for rendering ceramic powders hydrophobic that have a basic or amphoteric character.

Abstract: Rubber mixtures prepared from at least one styrene/butadiene rubber gel and at least one rubber which contains double bonds and optionally further fillers and rubber auxiliary substances are in particular suitable for the preparation of vulcanizates having unusually high damping at temperatures of from -20 to +20.degree. C. as well as unusually low damping at temperatures of from 40 to 80.degree. C. The rubber mixtures may therefore be used, for example, to manufacture vehicle tires which grip in the wet and have low rolling resistance.

Abstract: A ceramic layer system including at least two layers having respective ion conductivities which are substantially different includes a substrate layer composed of a ceramic material and having substantially no ion conductivity; and at least one conducting layer positioned adjacent to the substrate layer, containing coated ceramic particles composed of ceramic particles composed of a ceramic material having no substantial ion conductivity which are coated with a material having a substantial ion conductivity so that each conducting layer of the at least one conducting layer has a continuous phase after sintering composed of the material which has a substantial ion conductivity and so that the at least one conducting layer has an ion conductivity effective to conduct ions.

Abstract: The rubber mixtures according to the invention, containing at least one rubber, a filler, optionally additional rubber auxiliaries and at least one polysulphide polyether silane corresponding to the formulaR.sup.1 R.sup.2 R.sup.3 Si--X.sup.1 --(--S.sub.x --polyether --).sub.m --(--S.sub.x --X.sup.2 --SiR.sup.1 R.sup.2 R.sup.3).sub.n (I),are used for the preparation of rubber vulcanisates, from which in particular tires having a low rolling resistance associated with a good wet skid resistance and a high abrasion resistance can be produced.

Abstract: Rubber mixtures containing at least one rubber, one filler, optionally additional rubber auxiliary agents and also at least one sulphurous polyester are outstandingly suitable for the production of rubber vulcanisate having good mechanical properties and good hysteresis behaviour.

Abstract: A measuring sensor for determining oxygen content in a gas mixture including exhaust gases of internal combustion engines, includes a base substrate which is comprised of a base material and which is electrically insulating; and an electrochemical measuring probe and an electrochemical reference probe arranged separate from each other on the base substrate. The measuring probe includes at least one internal electrode; at least one solid electrolyte island; and at least one external electrode. The measuring probe additionally includes a diffusion barrier. Further base material layers composed of the base material are provided so as to embed at least the diffusion barrier, the at least one internal electrodes for the measuring probe and the internal electrode for the reference probe. A diffusion hole is defined between the measuring probe and the reference probe which extends from the base substrate through the diffusion barrier and respective base material layers, and out to the gas mixture to be measured.

Abstract: The rubber mixtures according to the invention, containing at least one vulcanising agent, a filler, optionally other rubber additives and at least one reinforcing additive of the formulaR.sup.1 R.sup.2 R.sup.3 Si--X.sup.1 --(--S.sub.x --Y--).sub.m --(--S.sub.x --X.sup.2 --SiR.sup.1 R.sup.2 R.sup.3).sub.nare used for the preparation of vulcanised rubbers, wherefrom in particular tires having a low rolling resistance combined with a good wet skid resistance and a high abrasion resistance can be produced.

Abstract: The invention relates to composite systems having at least two layers which comprise different inorganic, ceramic phases and are produced by cosintering of different, finely divided inorganic materials arranged in layers. The composite systems are characterized in that at least two adjacent layers comprise a dense phase largely free of macropores. The layers are durably bonded to one another by sintering together of particles of the different materials at the phase boundary or boundaries. The composite systems and the processes for the production thereof are used, for example, in the manufacture of gas sensors.

Abstract: Novel vulcanizable mixtures comprising silicone-core, acrylate-shell rubber particles dispersed within a fluorocarbon rubber.

Abstract: The invention relates to a process for the preparation of single-layered or multilayered molded articles from particles of polyisocyanate-polyaddition products by shaping a specified mixtures under heat and pressure. The mixture contains quasi-thermoplastic particles of polyisocyanate-polyaddition products and one or more processing aids.

Abstract: The invention relates to a measuring sensor having pump reference for measuring the oxygen content of gas mixtures, particularly exhaust gases of internal combustion engines. The sensor includes a measuring cell (A) and a reference cell (B) each having a pair of electrodes, with one of each respective pairs of electrodes being common to the two cells, and having a fixed electrolyte. Reference cell (B) has defined therein an internal oxygen reference zone which is hermetically sealed from the gas mixture and which is connected to the atmosphere by way of a pressure-equalization line. The measuring cell (A) and the reference cell (B) can be heated by heating apparatus to a temperature at which the fixed electrolyte has an ionic conductivity which is sufficiently high.

Abstract: The present invention relates to fluoropolymers with improved temperature resistance and dimensional stability in the heat based on fluoroethylenes, using perfluoro-(cycloalkyl-vinyl ethers) and optionally other monomers as comonomers. The invention also relates to the perfluor-(cycloalkyl-vinyl ethers) which impart the advantageous thermal properties to the fluoropolymers according to the invention.

Abstract: The rubber vulcanizates according to the invention, which are produced using certain carboxyalkyl oligosulfides, are distinguished by improved hysteresis behavior; their mechanical properties remain substantially unaffected.

Abstract: Rubber mixtures containing so-called "pre-crosslinked" polychloroprene give vulcanizates having an improved combination of low rolling resistance and low abrasion.

Abstract: The present invention relates to a process for the preparation of moldings or films based on polyisocyanate polyadducts comprising thermoplastically molding, at a temperature of at least 50.degree. C. and at a pressure of at least 5 bar, polyisocyanate polyadducts obtained by reacting in closed molds using the reaction injection molding technique aromatic polyisocyanates; compounds having a molecular weight of from 1800 to 12,000 and containing on a statistical average at least 2.5 isocyanate-reactive groups; and one or more components selected from a diamine containing two primary and/or secondary aromatically bound amino groups and and an aliphatic or cycloaliphatic polyol or polyamine; with the provisos that the quantity of isocyanate-reactive compound is at least 30% by weight based on the total quantity of the components and that at least one of the diamine, polyol, or polyamine components comprises at least 5% by weight based on the weight of the isocyanate-reactive compound.

Abstract: Vulcanizates of polychloroprene materials containing fluorinated polyolefin have a decreased rebound elasticity without having a significantly adverse effect on the mechanical properties.

Abstract: Thermoplastic elastomers made of 48 to 88% by weight of ethylene-propylene-diene-rubber (EPDM), 10 to 50% by weight of polypropylene (PP) and 2 to 20% by weight of a third polymer and 5 to 60% by weight of softening oil, based on the total of EPDM, PP and the third polymer, and optionally further conventional constituents, have the advantage that the softening oil does not exude.

Abstract: This invention relates to a polychloroprene elastomer distinguished by good processing properties and high tensile strength in the form of a polychloroprene mixture containing a sol polymer and a gel polymer in a ratio, by weight, of from 1:4 to 9:1, characterized in that both polymers have been produced in the presence of from 2.5 to 4.0 parts, by weight, of the potassium salt of disproportionated abietic acid (expressed as acid), from 0.3 to 1.0 part, by weight, of a condensation product of naphthalene sulphonic acid and formaldehyde and from 0.1 to 1.5 parts, by weight, of potassium hydroxide, based in each case on 100 parts, by weight, of monomer, and in that the gel polymer is a copolymer of chloroprene and from 1.5 to 2.5 mole percent, based on total monomer, of a diester corresponding to the following general formula: ##STR1## wherein R.sub.1 and R.sub.2 represent hydrogen, chlorine or C.sub.1 -C.sub.4 alkyl; andX represents C.sub.2 -C.sub.10 alkylene.