Abstract: The invention relates to polyisocyanates comprising urethane groups, based on toluylene diisocyanate, to a method for their production, and to their use as the polyisocyanate component in one- and two-component polyurethane coatings.

Abstract: A process for hydrogenating aromatic di- and polyamines is provided comprising the steps of reacting the aromatic amine with hydrogen in the presence of a catalytic system, wherein the catalytic system comprises a heterogeneous catalyst comprising a metal selected from the group consisting of Cr, Mo, W, Mn, Re, Fe, Ru, Os, Co, Rh, Ir, Ni, Pd and/or Pt and a support, and wherein the catalyst system further comprises an organic nitro compound. Hydrogenation of aromatic di- and polyamines having two or more amino groups bound to the aromatic ring produces cycloaliphatic di- and polyamines, which are useful chemical intermediates, e.g., for further reaction with epoxides or isocyanates. The amino groups may also be converted to isocyanates via reaction with phosgene. The resulting cycloaliphatic di- and polyisocyanates may also be used as monomers for making polymers.

Abstract: A catalytic process for hydrogenating aromatic di- and polyamines with the aid of a selected catalyst system is provided, which comprises a mixture of a first heterogeneous catalyst and a second heterogeneous catalyst and a nitro compound (nitrate and/or nitrite salt). The first and second heterogeneous catalyst each independently comprise a metal selected from the group consisting of Cr, Mo, W, Mn, Re, Fe, Ru, Os, Co, Rh, Ir, Ni, Pd and/or Pt and the metal selected for the second heterogeneous catalyst is different from the metal selected for the first heterogeneous catalyst. Hydrogenation of aromatic rings having two or more amino groups bound to the aromatic ring produces cycloaliphatic di- and polyamines, which are useful chemical intermediates, e.g., for further reaction with epoxides or isocyanates. The amino groups may also be converted to isocyanates via reaction with phosgene. The resulting cycloaliphatic di- and polyisocyanates may also be used as monomers for making polymers.

Abstract: The invention relates to compact, lightfast polyurethane moulded parts which consist of isocyanates, polyols and chain extenders and/or cross-linking agents, as well as to the use of same.

Abstract: A process for continuous preparation of oligomeric or polymeric isocyanates by catalytic modification of monomeric di- and/or triisocyanates, characterized in that at least one isocyanate component A and at least one catalyst component B are combined continuously in a reaction apparatus and conducted through the reaction apparatus as a reaction mixture, the residence time distribution being characterized according to the dispersion model by Bo (Bodenstein number) above 40, preferably above 60 and most preferably above 80.

Abstract: The invention relates to a process for preparing polyisocyanates containing isocyanurate groups by trimerising cycloaliphatic diisocyanates using a catalyst solution comprising at least one quaternary ammonium hydroxide, characterized in that the catalyst solution is metered in such that the reaction temperature is >90° C. and ?140° C.

Abstract: The invention relates to foamed lightfast polyurethane mouldings and to the use thereof.

Abstract: The invention relates to novel solvent-free, monomer-depleted polyisocyanate mixtures, and to the use thereof for producing light-resistant and weather-resistant polyurethane bodies with high optical refraction and low optical dispersion.

Abstract: The present invention relates to the use of solvent-free low-monomer polyisocyanates based on araliphatic diisocyanates for the production of light- and weather-resistant polyurethane bodies having a high light refraction and low dispersion.

Abstract: The present invention relates to an improved process for the preparation of polyisocyanates with a biuret structure by continuous reaction of excess amounts of organic diisocyanates having exclusively aliphatically and/or cycloaliphatically bonded isocyanate groups with organic diamines having exclusively aliphatically and/or cycloaliphatically bonded primary amino groups at elevated temperatures by 2-stage addition of the isocyanate component.

Abstract: The invention relates to the use of solvent-free modified polyisocyanate mixtures on the basis of araliphatic diisocyanates for producing light- and weather-resistant polyurethane bodies having light refraction and low dispersion.

Abstract: The invention relates to a new industrial process for producing low-monomer-content organic polyisocyanates by oligomerization of organic diisocyanates in a two-phase system.

Abstract: The invention relates to the use of specific pyridines as catalysts for the dimerization of isocyanates (uretdione formation) and a process for preparing polyisocyanates having a high content of uretdione groups.

Abstract: The invention relates to the use of heterocycles containing trivalent phosphorus as a ring member as catalysts for isocyanate modification and to a process for preparing polyisocyanates of the trimer type.

Abstract: The invention relates to the use of polyurethane casting compounds for producing light-resistant compact or expanded polyurethane or polyurethane urea bodies that are characterized by exceptionally good mechanical and visual properties and particularly have a very high heat shape retention.

Abstract: The invention relates to a process for preparing polyisocyanates having a high uretdione group content by phosphine-catalysed isocyanate oligomerization in the presence of organic carbonates and/or nitriles.

Abstract: The present invention relates to a process for modifying diisocyanates for preparing polyisocyanates, where the diisocyanate is reacted using a catalyst, wherein the diisocyanate used is obtained by quenching a gaseous reaction mixture in the phosgenation of diamines in the gas phase, wherein the gaseous reaction mixture comprises at least a diisocyanate, phosgene and hydrogen chloride, wherein a quenching liquid is sprayed into the gas mixture which flows continuously from a reaction zone into a downstream quenching zone, and wherein the quenching liquid is sprayed in by at least two spray nozzles which are arranged at the inlet of the quenching zone at equal intervals along the circumference of the quenching zone.

Abstract: The invention relates to polyisocyanates containing allophanate groups and silane groups, to a process for preparing them and to their use as a starting component in the production of polyurethane polymers, more particularly as a crosslinker component in polyurethane paints and coatings.

Abstract: The present invention relates to innovative polyisocyanate mixtures comprising cycloaliphatic structural elements and containing exclusively linear-aliphatically attached free isocyanate groups, to a process for preparing them and to their use as a starting component in the production of polyurethane plastics, more particularly as a crosslinker component in polyurethane coating materials and coatings.

Abstract: The present invention relates to polyurethane powder lacquers with optimized flow behavior, a process for their production, a process for coating substrates with these powder lacquers, as well as substrates coated with these powder lacquers.