Abstract: Metallocene compounds of the formula where CpI and CpII are carbanions having a cyclopentadienyl-containing structure, D is a donor atom and A is an acceptor atom, where D and A are linked by a reversible coordinative bond in such a way that the donor group takes on a positive (partial) charge and the acceptor group takes on a negative (partial) charge, M represents a transition metal of transition group III, IV, V or VI of the Periodic Table of the Elements (Mendeleev), X is one anion equivalent and n is, depending on the charge of M, zero, one, two, three or four, are new and can be used as catalysts for the (co)polymerization of olefins, i-olefins, alkines and/or diolefins or for ring-opening polyaddition. A typical X-ray structure analysis is represented by formula 18a.

Abstract: The present invention relates to a catalyst system comprising: a) an organoaluminum compound, b) a metal compound selected from subgroups IV to VI of the periodic system, c) a reactivator in a molar ratio of 0.5 to 100 relative to compound b), wherein said reactivator comprises a characterized in that a mono- or dihalocarboxylic acid alkyl ester of the following formula: wherein X is a C1-6 alkyl or C1-6 alkoxy group, Y is Cl, Br or H, Z is Cl or Br and R is a C1-6 alkyl group.

Abstract: A process for the recovery of an initially living polymer from a cement produced in a polymerization process. The living polymer cement is shortstopped, washed, stabilised, coagulated and dried. The recovery process comprises adding a short stop to the polymer in the cement, washing catalyst residue from the polymer with water, adding an antioxidant Irganox 1520 to the cement to stabilise the polymer, adding epoxidised soya bean oil to the polymer to stabilise the polymer against colour degradation, and coagulating and drying the polymer. The pH of the cement is regulated in the range of from about 3 to about 7, and preferably from about 6 to about 7, during the catalyst wash and the coagulation steps of the recovery process. A product of the process is also described.

Abstract: Surface-treated oxide or siliceous fillers are prepared by esterification of an oxide or siliceous filler with unsaturated compounds containing hydroxyl groups and treatment with sulfur or with sulfur donor, the reactions being carried out either in succession or together. The rubber mixtures obtained using these modified fillers are suitable for the production of highly reinforced, abrasion-resistant moldings, in particular for the production of tires having a low rolling resistance and high abrasion resistance.

Abstract: Thermoplastic elastomers can be prepared by (co)polymerization of monomers from the group consisting of C2-C8-&agr;-olefins, C4-C15-diolefins and other monomers in the bulk, solution, slurry or gas phase, the catalysts employed being metallocene compounds or the &pgr; complex compounds of the formulae in which CpI and CpII represent carbanions having a cyclopentadienyl-containing structure, &pgr;I and &pgr;II represent charged or electrically neutral &pgr; systems, D represents a donor atom and A represents an acceptor atom, where D and A are linked by a reversible coordinate bond such that the donor group assumes a positive (part) charge and the acceptor group assumes a negative (part) charge, M represents a transition metal of sub-group III, IV, V or VI of the Periodic Table of the Elements (Mendeleev), including the lanthanides and actinides, X denotes one anion equivalent and n denotes the number zero, one, two, three or four, depending on the charge of M.

Abstract: Elastomers can be prepared by (co)polymerization of monomers consisting of the group of C2-C8-&agr;-olefins, C4-C15-diolefins and other monomers in the bulk, solution, slurry or gas phase, the catalysts employed being metallocene compounds or the &pgr; complex compounds of the formula in which CpI and CpII represent carbanions having a cyclopentadienyl-containing structure, &pgr;I and &pgr;II represent charged or electrically neutral &pgr; systems, D represents a donor atom and A represents an acceptor atom, where D and A are linked by a reversible coordinate bond such that the donor group assumes a positive (part) charge and the acceptor group assumes a negative (part) charge, M represents a transition metal of sub-group III, IV, V or VI of the Periodic Table of the Elements (Mendeleev), including the lanthanides and the actinides, X denotes one anion equivalent and n denotes the number zero, one, two, three or four, depending on the charge of M.

Abstract: The present invention relates to the use of hollow microspheres filled with a hydrocarbon, to introduce uniform cell geometries in syntactic foams having a bimodal cell structure. The rigid foam product includes from 20 to 80 percent by weight of the hollow microspheres, the microspheres having average diameters ranging from 80 to 200 microns. The microspheres are encapsulated from 80 to 20 percent by weight of a closed cell polyurethane foam, the cells of the foam having average diameters from 0.01 to 60 microns.

Abstract: The present invention relates to a novel photochromic polyurethane consisting essentially of an isocyanate reactive mixture consisting essentially of: i) from about 40 to about 85% by weight of one or more polyols having a nominal functionality of from 2 to 4 and molecular weights of from 500 to 6000 g/mole; ii) from about 15 to about 60% by weight of one or more diols or triols or mixtures thereof having a functionality of from 2 to 3 and molecular weights of from 62 to 499; b) an aliphatic polyisocyanate having a functionality ranging from about 2 to about 3; and c) a photochromic compound selected from a group consisting of spirooxazines, fulgides, fulgimides, and naphthopyrans, wherein the photochromic compound is present in an amount of 0.01 to 5 parts per hundred parts by weight of the isocyanate reactive mixture.

Abstract: The present invention provides a process for preparing (4-nitroso-phenyl)phenyl-hydroxylamine which is characterized in that nitrobenzene is reacted in the presence of hydroxide and/or oxide-containing bases, optionally in the presence of solvents, at temperatures of 20 to 180.degree. C. and pressures of 0.1 to 10 bar.The process according to the invention has the particular advantage that it uses inexpensive and cost-effective nitrobenzene as starting material instead of the nitrosobenzene conventionally used hitherto.

Abstract: This invention relates to a process for the production of masterbatches which contain short fibres or pulps and which may be used for the production of polymer compositions or rubber compositions.

Abstract: Cycloolefin copolymers for industrial applications, with the exception of the use for optical data memories, can be prepared by copolymerization of monomers from the group consisting of cyclic olefins, .alpha.-olefins having 2 or more C atoms and optionally conjugated or non-conjugated diolefins, the catalysts employed being metallocene compounds or .pi. complex compounds of the formula ##STR1## in which CpI and CpII represent carbanions having a cyclopenadienyl-containing structure,.pi.I and .pi.II represent charged or electrically neutral .pi.

Abstract: The invention relates to new furfurylthioalkanes of the formula ##STR1## wherein n can be zero or 1R represents the methyl or ethyl radical if n is 0, and represents hydrogen or the methyl radical if n is 1, andR' represents methyl or ethyl,a process for their preparation and their use as aroma substances.

Abstract: A process and a device are described for the continuous production of block foam by the foaming of a mixture which reacts to form polyurethane and which contains carbon dioxide dissolved under pressure, wherein the pressure of the reactive mixture is reduced on passing through a pressure reduction zone in the form of an aperture, and blockage of the aperture is prevented by the relative movement of the aperture-delimiting faces with respect to each other.

Abstract: The invention concerns a heat-insulating body comprising: a) a pulverized hard foamed plastics material and optionally an inorganic porous material; and b) a foil enveloping component a). The foil enveloping component a) is evacuated and then hermetically sealed.

Abstract: This invention relates to the use of arylguanidinium xanthogenates as vulcanization accelerators, to a process for the production thereof and to the arylguanidinium xanthogenates.

Abstract: A process is described for the continuous production of polyurethane block foam using carbon dioxide which is physically dissolved under pressure as a foaming agent, wherein before the polyol and isocyanate components are mixed the carbon dioxide is dissolved in the polyol component and air or nitrogen is dissolved in the isocyanate component, both components are fed to a mixing chamber in which a pressure prevails which is 70 to 150% of the solution pressure of the CO.sub.2 in the polyol component, the isocyanate component is fed to the mixing chamber at a pressure of at least 30 bar and is injected therein with depressurization down to the mixing chamber pressure, wherein air or nitrogen in an amount of at least 1 g per kg CO.sub.2 is dissolved in the isocyanate component, and after emerging from the mixing chamber the mixture is depressurization to atmospheric pressure.

Abstract: The invention relates to a new process for the preparation of dithiazolyl-(2,2')-disulfides by oxidation of 2-mercaptothiazoles, to the dithiazolyl-(2,2')-disulfides that can be obtained in this way, and to the use thereof.

Abstract: The apparatus for treating viscous substances described is composed of a heatable vessel with, on one side, an inlet for the materials of the mix and, on the other side, an outlet for the materials of the mix and of two or more corotating shafts to which mixer elements have been attached, characterized in that the mixer elements are composed of two layers of bars, which are arranged crosswise in relation to each other, connected to one another. There are pins running axially attached to the face sides of the bars. These clean the interstices between the bars of the mixer elements of the adjacent shaft.

Abstract: A multilayer flat molding with a visible side and a supporting layer, for example bathtubs or shower fittings, is described, the visible side consisting of a polyurethane surface coating layer and the supporting layer consisting of a reinforced polyurethane layer.

Abstract: The present invention relates to a novel photochromic polyurethane consisting essentially of an isocyanate reactive mixture consisting essentially of: i) from about 40 to about 85% by weight of one or more polyols having a nominal functionality of from 2 to 4 and molecular weights of from 500 to 6000 g/mole; ii) from about 15 to about 60% by weight of one or more diols or triols or mixtures thereof having a functionality of from 2 to 3 and molecular weights of from 62 to 499; b) an aliphatic polyisocyanate having a functionality ranging from about 2 to about 3; and c) a photochromic compound selected from a group consisting of spirooxazines, fulgides, fulgimides, and naphthopyrans, wherein the photochromic compound is present in an amount of 0.01 to 5 parts per hundred parts by weight of the isocyanate reactive mixture.