Abstract: Magnetorheological formulations, processes for preparing the same and uses therefor, the formulations comprising: (a) an ionic liquid comprising anions and cations, and (b) dispersed magnetizable particles having a mean diameter of 0.

Abstract: The invention relates to a rheometer having a rotatable shaft (1) on which a rotor plate (2) is fastened, and having a measuring instrument (10) for measuring torques exerted on the rotor plate (2) by a substance (6) to be studied during rotation of the shaft (1), a first measurement gap (5) for holding the substance (6) to be studied being formed between a first side (3) of the rotor plate (2) and a first shear face (4) and a second measurement gap (9) for holding the substance (6) to be studied being formed between a second side (7) of the rotor plate (2), opposite the first side, and a second shear face (8). The rheometer contains a magnet for generating a magnetic field in the first and second measurement gaps (5, 9).

Abstract: A magnetorheological formulation which comprises at least one base oil, at least one magnetizable particle, a at least one dispersant and a at least one thixotropic agent is described.

Abstract: A method for characterizing magnetorheological fluids using a volume flow rate measurement. The volume flow of the magnetorheological fluid through a capillary is initially measured, with a constant weight force being applied onto the magnetorheological fluid. A magnetic field is then applied to the capillary, and the volume flow of the magnetorheological fluid through the capillary is measured with the magnetic field applied, with a second constant weight force being applied onto the magnetorheological fluid. A device for carrying out the method comprises a container for storing a magnetorheological fluid, wherein the container is connected on one side to a capillary through which the magnetorheological fluid can flow, and is closed on a different side by a movable piston, which presses the magnetorheological fluid through the capillary with a constant weight force, and means for generating a magnetic field are provided in the region of the capillary.

Abstract: The invention relates to a rheometer having a rotatable shaft (1) on which a rotor plate (2) is fastened, and having a measuring instrument (10) for measuring torques exerted on the rotor plate (2) by a substance (6) to be studied during rotation of the shaft (1), a first measurement gap (5) for holding the substance (6) to be studied being formed between a first side (3) of the rotor plate (2) and a first shear face (4) and a second measurement gap (9) for holding the substance (6) to be studied being formed between a second side (7) of the rotor plate (2), opposite the first side, and a second shear face (8). The rheometer contains a magnet for generating a magnetic field in the first and second measurement gaps (5, 9).

Abstract: Methods comprising: providing a suspension comprising magnetizable particles; and delivering the suspension through a gap (3), wherein a magnetic field is applied in the gap, such that the suspension is sheared in the gap in the presence of the magnetic field to form a conditioned suspension; and devices for conditioning suspensions containing magnetizable particles, the device comprising a gap (3) through which the suspension containing magnetizable particles flows and in which a shear force is applied to the suspension containing magnetizable particles, wherein the device furthermore contains a magnet for generating a magnetic field in the gap (3).

Abstract: The invention relates to a constant load shear cell and a method for constant loading of a magnetorheological fluid in a constant load shear cell. The constant load shear cell comprises a rotatable shaft (1), to which a rotor plate (2) is fixed. A first gap (5), for accommodating a magnetorheological fluid, is formed between a first side (3) of the rotor plate (2) and a first shear surface (4). A second gap (8), for accommodating the magnetorheological fluid, is formed between a second side (6) of the rotor plate (2) facing away from the first and a second shear surface (7). The constant load shear cell further comprises at least one magnet (9) for generating a magnetic field in the first and second gaps (5, 8).

Abstract: A process for the preparation of expandable styrene polymers having a molecular weight Mw of greater than 170,000 g/mol, which comprises conveying a blowing agent-containing styrene polymer melt having a temperature of at least 120° C. through a die plate with holes whose diameter at the die exit is at most 1.5 mm, and subsequently granulating the extrudate, and expandable styrene polymers (EPS) having a molecular weight Mw of more than 170,000 g/mol with 0.05 to 1.5% by weight of internal water.

Abstract: A magnetorheological formulation which comprises at least one base oil, at least one magnetizable particle, a at least one dispersant and a at least one thixotropic agent is described.

Abstract: Magnetorheological formulations, processes for preparing the same and uses therefor, the formulations comprising: (a) an ionic liquid comprising anions and cations, and (b) dispersed magnetizable particles having a mean diameter of 0.

Abstract: A process for the preparation of expandable styrene polymers having a molecular weight Mw of greater than 170,000 g/mol, which comprises conveying a blowing agent-containing styrene polymer melt having a temperature of at least 120° C. through a die plate with holes whose diameter at the die exit is at most 1.5 mm, and subsequently granulating the extrudate, and expandable styrene polymers (EPS) having a molecular weight Mw of more than 170,000 g/mol with 0.05 to 1.5% by weight of internal water.

Abstract: Biodegradable polyesters based onA) 95-99.99 mol % of at least one polyester A containing as monomeric building blocks of an acid component comprisinga.sub.11) 20-95 mol % of at least one aliphatic or cycloaliphatic dicarboxylic acid or its ester-forming derivative anda.sub.12) 5-80 mol % of at least one aromatic dicarboxylic acid or its ester-forming derivative andat least one dihydroxy compound or at least one amino alcohol or their mixtures, andB) 0.01-5 mol % of a mixture comprising mono-, bi-, tri-, tetra- and higher-nuclear isocyanurates or corresponding compounds containing two, three or four functional groups capable of reacting with the end groups of polyester A, or mixtures of the isocyanurates and the corresponding compounds,as well as molding compositions comprising said polyesters, their manufacture and their use in the manufacture of moldings, filsm, fibers and coatings.

Abstract: Polyamides are built up from, as fundamental building blocks (a), lactams or aminocarboxylic acids or mixtures of these,as fundamental building blocks (b), from 1 to 50 .mu.mol of at least tribasic amines or carboxylic acids per gram of polyamide,as fundamental building blocks (c), dibasic carboxylic acids or amines andas fundamental building blocks (d), monobasic carboxylic acids or amines,where (c) and (d) are carboxylic acids if (b) are amines, and (c) and (d) are amines if (b) are carboxylic acids,the equivalents ratio of the functional groups of (b) to the functional groups of (c) and (d) together is from 60:40 to 40:60 andthe equivalents ratio of the functional groups of (c) to the functional groups of (d) is from 15:85 to 60:40.

Abstract: Branched polyamides are prepared by mixingA) from 10 to 99.7% by weight of a melt of a polyamide prepolymer having a viscosity number of from 40 to 90 ml/g withB) from 0.3 to 6% by weight of a polybasic carboxylic acid, where the number n of the free carboxylic acid groups is 3.ltoreq.n.ltoreq.10, and alsoC) from 0 to 80% by weight of further additives and processing aids,where the percentages by weight of the components A) to C) add up to 100%, and subsequently further condensing the mixture in the solid phase.

Abstract: A magnetorheological fluid essentially consists of magnetic particles which are coated with a polyelectrolyte and are suspended in a polar liquid. The fluid has a magnetorheological effect of more than 100 Pa, measured in a magnetic field of 100 kA/m.

Abstract: The invention relates to a process and device for measuring the effective viscosity and the elastic properties of coatings. Known measuring processes and measuring devices based on the "rolling ball method" suffer from drawbacks, namely run formation and sinking of the relatively heavy solvent vapors, due to the inclination of the coated sheet metal. To overcome these drawbacks, rolling movements are imparted to a magnetizable ball (1) displaced from its rest position in a magnetic field, during movement of the horizontally disposed substrate, under the influence of the field gradient of a permanent magnet or electromagnet (4) located below the substrate. The rolling movements are used as the basis for the measurements.

Abstract: A highly dilatant copolymer dispersion containing, as essential components, an emulsion copolymer prepared from 1 to 10% by weight, based on the sum of the monomers employed, of .alpha.,.beta.-monoolefinically unsaturated carboxylic acids and other olefinically unsaturated monomers, in which the emulsion copolymer is prepared in the presence of from 5 to 30% by weight, based on the sum of the monomers employed, of allyl carboxylate or alkylallyl carboxylate containing 2 or more copolymerizable olefinic double bonds, or a mixture thereof, the alkyl radical containing 1 to 4 C atoms, and the preparation thereof.

Abstract: .alpha.-Monoolefins are polymerized using a Ziegler catalyst system comprising (1) a transition metal catalyst component and (2) an organoaluminum catalyst component, in which (1) is a solid-phase product (VI) obtained by (1.1) first combining (1.1.1) an inorganic oxidic substance (I), as the carrier, with (1.1.2) a solution (II) consisting of (IIa) an organic solvent and (IIb) a transition metal composition to form a suspension (III), evaporating down this suspension to form a solid-phase intermediate (IV), and (1.2) then (1.2.1) combining the solid-phase intermediate (IV), obtained from (1.1), with (1.2.2) a solution of an organoaluminum compound (V) to form a suspension, the resulting suspended solid-phase product (VI) being the transition metal catalyst component (1).

Abstract: A dispersion, having highly dilatant flow, of a carboxyl-containing copolymer of monoolefinically unsaturated monomers, wherein the temperature dependence of the critical shearing rate is greatly reduced by incorporation of from 0.1 to 30% by weight of oxides, hydroxides, carbonates and/or water soluble salts of monovalent or divalent metals.