Abstract: The invention provides a process for preparing polyesters by reacting an H-functional starter substance with a lactone in the presence of a Brønsted-acidic catalyst which comprises initially charging the H-functional starter substance and the Brønsted-acidic catalyst to form a mixture i) and subsequently adding the lactone to the mixture i), wherein the process is carried out without adding an aromatic solvent and wherein the H-functional starter substance is an OH-functional starter substance and/or a COOH-functional starter substance and wherein the lactone is a 4-membered ring lactone. The invention further provides polyesters obtainable by the method of the invention.

Abstract: The present invention relates to open- and fine-celled rigid polyurethane foams which contain not only urethane groups (PUR) but also isocyanurate groups (PIR) and carbodiimide groups (CD) and to the use thereof in vacuum insulation panels.

Abstract: The present invention relates to the use of hydrophopic polyols for producing fiber composite components on the basis of a polyurethane/polyisocyanurate reaction mixture, to a method for producing composite components and to the composite components as such. The method according to the invention is particularly economical in terms of saving material and time costs and the composite components obtained are characterized by excellent visual and material properties.

Abstract: The present invention relates to a special process for preparing polyesterols having terminal hydroxyl groups and containing imide groups, to the polyesters per se, and to their use for the preparation of polyurethanes.

Abstract: The present invention relates to a process for producing an open-cell rigid polyurethane foam. Said foams can contain, besides urethane groups (PUR), also isocyanurate groups (PIR).

Abstract: The invention relates to high-temperature-resistant foams having excellent flame retardancy, to the production thereof from organic polyisocyanates and polyepoxides, and to the use of said foams.

Abstract: The present invention relates to sheet-form fiber composite components which are obtainable by impregnating fibers with a reactive resin mixture comprising polyisocyanates, polyepoxides, polyols and optionally additives, and to a process for the production thereof.

Abstract: The present invention relates to the use of hydrophopic polyols for producing fiber composite components on the basis of a polyurethane/polyisocyanurate reaction mixture, to a method for producing composite components and to the composite components as such. The method according to the invention is particularly economical in terms of saving material and time costs and the composite components obtained are characterized by excellent visual and material properties.

Abstract: The present invention relates to fiber-composite components that are produced by impregnating fibers with a reaction resin mixture of polyisocyanates, polyols, trimerization catalysts and optionally additives, and to a method for production thereof.

Abstract: The invention relates to the use of layer structures in the production of rotor blades for wind power plants, and to rotor blades for wind power plants.

Abstract: The present invention relates to fibre-composite components that are produced by impregnating fibres with a reaction resin mixture of polyisocyanates, polyols, trimersation catalysts and optionally additives, and to a method for production thereof.

Abstract: The present invention relates to fibre composite alloys which can be obtained by impregnation of fibres with a reactive resin mixture of polyisocyanates, dianhydrohexitols, polyols and optionally additives, and also a process for the production thereof.

Abstract: The invention relates to the use of layer structures in the production of rotor blades for wind power plants, and to rotor blades for wind power plants.

Abstract: The present invention relates to sheet-form fibre composite components which are obtainable by impregnating fibres with a reactive resin mixture comprising polyisocyanates, polyepoxides, polyols and optionally additives, and to a process for the production thereof.

Abstract: The present invention concerns a method for the treatment of polyurethane foam, wherein the polyurethane foam is obtainable from a reaction mixture comprising an ethylene oxide/propylene oxide polyol component with an OH number of ?20 mg KOH/g to ?45 mg KOH/g and an isocyanate component with an NCO content of ?20 weight-% to ?49 weight-% which is selected from the group comprising diphenylmethane diisocyanate, toluene diisocyanate, their prepolymers with an ethylene oxide/propylene oxide polyol whose OH number is from ?20 mg KOH/g to ?45 mg KOH/g and/or their allophanates, ureas, biurets, uretdiones, isocyanurates or carbodiimides. The invention further concerns a polyurethane foam which has been treated by such a method. After the foam formation has finished, the polyurethane foam is irradiated with microwave radiation and the irradiated energy, in relation to the volume accessible by the microwave radiation, is from ?1.0 kilojoules/liter to ?2.23 kilojoules/liter.

Abstract: The present invention relates to an improved process for the preparation of NCO-reactive components from fully reacted products of the isocyanate polyaddition process, in particular those based on MDI and/or TDI, using reactive solvents in a microwave field.

Abstract: The present invention relates to a process for the accelerated preparation of polyesterpolyols in equilibrium by alcoholysis using microwave radiation, and to the production foamed and non-foamed polyurethane materials from these polyesterpolyols.