Abstract: Coating compositions that are stable to thermal yellowing that include coating materials containing I) one or more dispersions of hydroxyl-free polyurethanes and/or polyurethane-ureas, II) one or more aqueous solutions or dispersions of ionically modified, hydroxyl-containing polyurethanes and/or polyurethane-ureas, other than the constituents of component I), and III) at least one crosslinker.

Abstract: A process for the preparation of polycarbonate by the phase boundary process is disclosed. The process entails reacting at least one dihydroxydiarylalkane in the form of its alkali metal salts with phosgene in the heterogeneous phase in the presence of sodium hydroxide solution and an organic solvent. The process is characterized in that the feedstock have but low content of Fe, Cr, Ni, Zn, Ca, Mg, Al metals or homologues thereof, and in that the organic solvent is separated off, and in that the polycarbonate which is obtained is worked up. The resulting polycarbonate is particularly useful in producing transparent shaped articles.

Abstract: The present invention is directed to a process for the production of polyisocyanates containing isocyanurate groups by trimerizing a portion of the isocyanate groups of hexamethylene diisocyanate using N,N,N-trialkyl-N-benzyl-quaternary ammonium hydroxides as the trimerization catalyst, terminating the trimerization reaction at the desired degree of trimerization by adding a catalyst poison and/or by thermally deactivating the catalyst and removing unreacted hexamethylene diisocyanate to a residual content of at most 0.2% by weight, characterized in that a) the hexamethylene diisocyanate used as starting material is freed from carbon dioxide to a residual content of less than 20 ppm (weight) and b) the catalyst is used in a quantity of less than about 0.03% by weight, based on the weight of the hexamethylene diisocyanate used.

Abstract: This invention relates to a process for the production of dithiophosphoric acid poly-sulfide mixtures, which is characterized in that dithiophosphoric acid disulfides are reacted with sulfur at elevated temperatures. The dithiophosphoric acid polysulfide mixtures produced using the process according to the present invention are used as sulfur donors for the vulcanization of natural and synthetic rubbers and in the latex vulcanization of natural and synthetic rubber latex.

Abstract: The present invention relates to novel aromatic isocyanates obtained by partially hydrogenating naphthalene as well as the processes for preparing the same, and to their use as an isocyanate component in the production of polyurethanes.

Abstract: A vulcanizate derived from a polymer composition comprising three components exhibits improved hot air aging properties and is useful, for example, for the manufacture of articles subject to dynamic loading, such as belting applications. The first component is a polymer having a main polymer chain derived from: (i) at least about 30% by weight of a first monomer which introduces at least one of a secondary carbon and a tertiary carbon to the backbone, and (ii) from 0 to about 70% by weight of at least one other monomer. Preferred are ethylene-alpha-olefin copolymers. The second component is a salt of a strong base and a weak acid, the salt comprising a metal selected from Group I of the Periodic Table of Elements. The third component is an antioxidant.

Abstract: The invention relates to rubber compounds comprising at least one double bond-containing rubber, additions of rubber gels, phenolic resin adducts or phenol/formaldehyde condensation products, such as resols or novolaks, and optionally, further fillers and rubber auxiliary substances, and the vulcanizates and molded rubber articles produced from them. The rubber compounds according to the present invention are characterized in the uncrosslinked state by good processability (compound viscosity ML 1+4/100° C.<60 ME) and in the vulcanized state by Shore-A hardness values/23° C.>60, high impact resilience values E/23° C.>60% and a low specific density. The vulcanizates are suitable for the production of industrial rubber articles and for various tire components, such as roll coverings, conveyor belt coverings, belts, spinning cops, seals, golf ball cores, shoe soles and bead compounds, tire carcasses, subtread compounds and tire sidewalls.

Abstract: The block copolymers according to the invention which are based on conjugated diolefins and polar monomers and are prepared in the presence of catalysts based on the rare earth metals have a high cis-1,4 content in the polydiene block and, because of their polar polymer part and their non-polar diene polymer part, can be used as agents which impart compatibility in the preparation of vulcanizates with a filler content for the production of tires and tire component in the preparation of thermoplastic elastomers or in the modification of thermoplastics.

Abstract: The invention relates to rubber compounds that contain rubbers polymerized in solution with a secondary hydroxyl group content of 0.1 to 5 wt.- % that are not more than 4 carbon atoms away from the respective side chain end. The invention also relates to mixtures thereof with fillers, optionally additional rubbers and rubber auxiliary agents and the vulcanized rubbers produced thereof. The inventive rubber compounds are useful for producing highly reinforced, abrasion-resistant molded bodies, especially for producing tires that are characterized by excellent non-skid properties on wet surfaces.

Abstract: The present invention relates to rubber mixtures containing diene rubber with a concentration of primary hydroxyl groups of 0.1 to 2 wt. % and a glass transition temperature of −120° to −50° C. and their mixtures with fillers, optionally further rubbers and rubber auxiliary substances and vulcanisates prepared therefrom. Rubber mixtures according to the invention are suitable for producing highly reinforced, abrasion-resistant moulded items, in particular for producing tires treads which have a particularly high resistance to wet skidding.

Abstract: A process is described for producing foam materials from two-component reactive plastics using carbon dioxide as blowing agent by mixing at least one of the reactive components with carbon dioxide under pressure, mixing the components, at least one of which contains carbon dioxide under pressure, expanding the reactive mixture containing carbon dioxide obtained by mixing, and hardening, wherein the expansion takes place suddenly with the production of high rates of shear. Preferably the rate of flow of the reaction mixture is reduced after expansion.

Abstract: The present invention provides a process of hydrogenating a nitrile copolymer rubber, which comprises subjecting the copolymer to hydrogenation in the presence of a hydrogenation catalyst, a co-catalyst, and a proton acceptor that is non-coordinating with the metal-complex catalyst.

Abstract: The present invention provides a novel process for the preparation of isoolefin copolymers in the presence of zirconium halides and/or hafnium halides and organic acid halides, in particular for the preparation of butyl rubbers, as well as isoolefin copolymers constructed of isobutene, isoprene and optionally further monomers.

Abstract: The present invention relates to compounds in which a transition metal is complexed with two ligand systems and the two systems are reversibly bonded together by at least one bridge consisting of a donor and an acceptor, at least one substituent on the acceptor group being a fluorinated aryl radical, to the use of these compounds as catalysts and to a process for the polymerization of olefins.

Abstract: The rubber mixtures according to the present invention consisting of uncrosslinked, double bond-containing rubbers (A), crosslinked rubber particles (B) and multifunctional isocyanates based on polyuret (C), wherein, based on 100 parts by weight (phr) of the rubber components (A) respectively, the component (B) content in the mixture is 1 to 150 parts by weight and the multifunctional isocyanate content based on polyuret (component C) is 1 to 100 parts by weight, can be used to produce rubber vulcanizates and rubber molded articles of all kinds, the vulcanizates produced therefrom exhibiting an advantageous combination of mechanical properties, such as modulus at 300% elongation, elongation at break, tear strength and abrasion resistance.

Abstract: A process is provided for the removal of iron- and rhodium-containing residues from a solution of hydrogenated nitrile rubber. The process utilizes an ion-exchange resin having thiourea functional groups. Further, the resin is both macroporour and monodispersed. The process removes both rhodium and iron from viscous rubber solutions. In a preferred embodiment, the process is carried out in an ion-exchange column.

Abstract: A thermoplastic molding composition that contains an aliphatic thermoplastic polyurethane (TPU) resin is disclosed. The TPU is the product of a reaction of A) a diisocyanate reactant that contains predominantly hexamethylene diisocyanate, and B) a polyol reactant that contains polytetramethylene glycol and C) a chain extending reactant that contains primarily 1,6-hexanediol. The TPU that is further characterized in the equivalence ratio of A to B and NCO index exhibits improved properties.

Abstract: A process for preparing a butyl polymer, the process comprising contacting a C4 to C8 monoolefin monomer with a C4 to C14 multiolefin monomer at a temperature in the range of from about −100° C. to about +50° C. in the presence of a diluent and a catalyst mixture comprising a monoalkylaluminum dihalide and an aluminoxane.

Abstract: This invention relates to covulcanizable anti-aging agents which can be produced by the reaction of p-phenylenediamines, which are optionally substituted, and/or of sterically hindered phenols, with bifunctional alkyl, aryl and/or aralkyl compounds and by subsequent reaction of the products thus obtained with sulfur and/or sulfur donor compounds. The anti-aging agents according to the present invention maintain their efficacy over a long period of time and are distinguished in particular by the fact that in practice, they are hardly extracted from the vulcanized products by water, by oil and/or petrol, or by hydraulic fluids.

Abstract: The vulcanizates produced using the rubber mixtures according to the invention, in which the vulcanizates contain agglomerated rubber gels, are distinguished by improved mechanical properties with an at least equivalent damping behavior.