Abstract: The present invention relates to polyol dispersions with long-term stability, to cellular polyurethane moldings produced therewith, to processes for their preparation and to their use.

Abstract: The present invention relates to polyol dispersions with long-term stability, to cellular polyurethane moldings produced therewith, to processes for their preparation and to their use.

Abstract: Solid polyurethane moldings having high inherent rigidity, thin walls and a complex geometry are produced. These polyurethane moldings can be produced by reacting a selected polyisocyanate with a selected compound having groups that are capable of reacting with isocyanate groups by means of the casting process which is a simple and inexpensive processing technology.

Abstract: The present invention relates to a process for the production of polyurethane foam moldings having a compact surface skin and a density of at least 150 kg/m.sup.3 comprising foaming a polyurethane-forming starting mixture inside a mold. The starting mixture comprises organic blowing agents which correspond to one or both of the following general formulas:HOOC--R--COOH (I)wherein: R represents a CH.sub.2 group or a CH.dbd.CH group;and ##STR1## wherein: R.sup.1 and R.sup.2 independently of one another represent either a hydrogen atom or a C.sub.1-6 alkyl radical wherein the hydrogen atoms may be partly substituted by OH groups.

Abstract: Polyol mixtures containing a mixture of internal mold release agents which are storage stable are made up of (a) from about 55 to about 95% by weight of a polyol mixture of (1) 30-70% by weight of at least one polyol with an OH value of more than 700 and (2) from about 30 to about 70% by weight of at least one polyol with an OH value of 700 or less than 700 and (b) from about 5 to about 45% by weight of a mixture of internal mold release agents made up of (1) from about 60 to about 95% by weight of at least one salt-like release agent and (2) from about 5 to about 40% by weight of at least one non-salt-like release agent containing an amide NH function or a urethane NH function. Known auxiliaries and additives may optionally be included. These polyol mixtures are useful in the production of rigid, semirigid and flexible polyurethane materials, particularly molded polyurethanes.

Abstract: A process for the production of composite bodies of polyurethane foams and covering layers, which includes at least partly lining a mold with a covering layer, and filling the mold with a reaction mixture which reacts to form a polyurethane foam. The reaction mixture which forms a polyurethane foam consists of a polyisocyanate component, a component consisting of at least one organic compound having at least two isocyanate reactive groups, blowing agents, and salts with water of crystallization as additives for improving the bond between the foam and the covering layer.

Abstract: The present invention is directed to a process for the preparation of molded polyurethane articles having densities of about 0.8 to 1.4 g/cm.sup.3 and a flex moduli according to DIN 53,457 of at least about 1800 N/mm.sup.

Abstract: The present invention is directed to a process for the production of molded polyurethane foams having a compact surface and a density of at least 250 kg/m.sup.3 by the in-mold foaming of a reaction mixture containinga) a polyisocyanate component containing at least one aromatic polyisocyanate,b) an isocyanate-reactive component containing at least one organic compound having at least two isocyanate-reactive groups andc) a blowing agentat an isocyanate index of 75 to 1500, characterized in that organic carboxylic acids are used as blowing agents c), optionally in addition to other chemical or physical blowing agents.The present invention is also directed to the molded polyurethane foams obtained by this process.

Abstract: The present invention relates to a process for the production of fluorocarbon-free, rigid polyurethane foam moldings having a gross density of at least 300 kg/m.sup.3 by in-mold foaming of a reaction mixture based on(a) a polyisocyanate component containing at least one aromatic polyisocyanate,(b) a polyhydroxyl component,(c) blowing agents,(d) catalysts and(e) zeolitic adsorbents,at an isocyanate index of about 75 to 150, characterized in that(b) an organic polyhydroxyl compound or a mixture of organic polyhydroxyl compounds having an (average) hydroxyl functionality of at least 2.2 and an (average) OH number of at least 300 mg KOH/g is used as the polyhydroxyl component,(c) water and/or carbon dioxide is/are used as the blowing agent and(e) the zeolitic adsorbents have a pore diameter of at least 0.7 nm.