Abstract: The present invention relates to composite elements comprising (i) plastic, adhering to which there is (ii) a polyisocyanate polyaddition product, where the polyisocyanate polyaddition product is obtained via mixing of (a) isocyanate with (b) compounds having groups reactive toward isocyanates, (c) catalysts and optionally additional products to give a reaction mixture and converting the reaction mixture to a polyisocyanate polyaddition product, where the compounds (b) comprise a polyester polyalcohol as adhesion promoter, capable of production via polycondensation of an acid component and one or more low-molecular-weight diols whose molar mass is less than 500 g/mol, in excess, where the acid component comprises from 83 to 97 mol % of adipic acid and from 3 to 17 mol % of phthalic acid, isophthalic acid, and/or terephthalic acid. The present invention also relates to components in the fitting-out or aircraft, of vehicles, or of buildings, and to insulation comprising this type of composite element.

Abstract: The subject of the present invention is a process for preparing polyester alcohols by condensation of polytetrahydrofuran with aromatic dicarboxylic acids and/or their anhydrides in the presence of a transesterification catalyst in a multi-stage operation at different pressure levels with at least one reaction stage at atmospheric pressure and at least one reaction stage at reduced pressure, where distillate is removed from the reaction system, which process comprises heating the reaction mixture in two or more phases in the atmospheric-pressure reaction stage wherein the heating phases are interrupted by at least one phase in which the temperature is kept constant.

Abstract: The present invention relates to composite elements comprising (i) plastic, adhering to which there is (ii) a polyisocyanate polyaddition product, where the polyisocyanate polyaddition product is obtained via mixing of (a) isocyanate with (b) compounds having groups reactive toward isocyanates, (c) catalysts, (d) if appropriate, blowing agent, and (e) if appropriate, further additives, to give a reaction mixture and permitting the reaction mixture to complete its reaction to give the polyisocyanate polyaddition product, where the compounds (b) having groups reactive toward isocyanates comprise a polyester polyalcohol as adhesion promoter, capable of production via polycondensation of an acid component and of one or more low-molecular-weight diols whose molar mass is less than 500 g/mol, in excess, where the acid component comprises from 83 to 97 mol % of adipic acid and from 3 to 17 mol % of phthalic acid, isophthalic acid, and/or terephthalic acid.

Abstract: Polyester polyol comprising the esterification product of a) from 10 to 70 mol % of a dicarboxylic acid composition comprising a1) from 50 to 100 mol % of a material based on terephthalic acid, selected from among terephthalic acid, dimethyl terephthalate, polyalkylene terephthalate and mixtures thereof, a2) from 0 to 50 mol % of phthalic acid, phthalic anhydride or isophthalic acid, a3) from 0 to 50 mol % of one or more dicarboxylic acids, b) from 2 to 30 mol % of one or more fatty acids and/or fatty acid derivatives and/or benzoic acid, c) from 10 to 70 mol % of one or more aliphatic or cycloaliphatic diols having from 2 to 18 carbon atoms or alkoxylates thereof, d) from 2 to 50 mol % of a higher-functional polyol selected from the group consisting of glycerol, alkoxylated glycerol, trimethylolpropane, alkoxylated trimethylolpropane, pentaerythritol and alkoxylated pentaerythritol, wherein at least 200 mmol, preferably at least 500 mmol and particularly preferably at least 800 mmol, of polyols d) havin

Abstract: The invention provides a process for preparing polyester polyols of polyhydric alcohols by mono- or polyesterification of at least one carboxylic acid having at least two acid groups and/or at least one derivative of a dicarboxylic acid with polyhydric alcohols, optionally with the addition of a catalyst, while removing the water of reaction, wherein the polyhydric alcohol used has a formaldehyde acetal content of less than 500 ppm.

Abstract: The invention provides a process for preparing polyester polyols of polyhydric alcohols by mono- or polyesterification of at least one carboxylic acid having at least two acid groups and/or at least one derivative of a dicarboxylic acid with polyhydric alcohols, optionally with the addition of a catalyst, while removing the water of reaction, wherein the polyhydric alcohol used has a formaldehyde acetal content of less than 500 ppm.

Abstract: Polyester-polyether block copolymers can be prepared by catalytic addition of alkylene oxides onto H-functional initiator substances, using polyester alcohols as H-functional initiator substances and multimetal cyanide compounds as catalysts.

Abstract: Aqueous dispersions containing a polyurethane built up froma) diisocyanates having 4 to 30 carbon atoms,b) diols, of whichb.1) from 10 to 100 mol %, based on the total amount of the diols (b), have a molecular weight of from 500 to 5000 and are built up fromb1.1) (C.sub.4 - to C.sub.30 -alkyl)succinic acid and/or (C.sub.4 - to C.sub.30 -alkenyl)succinic acid,b1.2) from 0 to 60 mol %, based on component (b1.1), of a dicarboxylic acid which is different from component (b1.1), andb1.3) a diol having a molecular weight of from 60 to 500 g/mol,b.2) from 0 to 90 mol %, based on the total amount of the diols (b), have a molecular weight of from 60 to 500 g/mol, andb.