Abstract: The present invention relates to polyol mixtures which are suitable for the preparation of rigid polyurethane foams and comprise addition products of alkylene oxide on aromatic di- or polyamines, and rigid foams prepared with these polyol mixtures.

Abstract: A covering arrangement (10) for a building has parallel elongate supports (14) and covering parts (16) arranged thereon. The covering parts comprise a core (22) and, connected thereto, upper covering elements (24) and lower planar covering elements (26), with the result that a sandwich is formed. The covering parts (16) furthermore have an elongate, striplike form and in the installed position are arranged transversely to the supports (14), extending at least from one support (14) to a neighbouring support (14). In order to increase the resistance to wind loads, it is proposed that a longitudinal border region (30) of a covering part (16) comprises a connecting device (68) and the opposite longitudinal border region (34) of a neighbouring covering part (16) has a connecting device (70) complementary thereto, by means of which the two covering parts (16) are firmly connected to each other.

Abstract: Compressed polyurethane or polyisocyanurate foams useful as support materials for vacuum insulation units are produced by compressing an open-cell rigid polyurethane or polyisocyanurate to 5-95% of its original volume after 80-200% of the fiber time.

Abstract: A process for the production of rigid polyurethane foams having low thermal conductivity is described.

Abstract: Closed cell rigid polyurethane foams are produced by reacting a) a polyol component with b) a polyisocyanate having an NCO content of from about 20 to about 48% by weight.

Abstract: A process for preparing polyurethane rigid foams from polyols and polyisocyanates as well as blowing agents and optionally foam auxiliary agents, characterized in that the polyurethane rigid foam is obtained by reactingA) a polyol component with on average at least 3 hydrogen atoms, containing1. 60 to 100% of polyethers and/or polyesters with at least 2 hydroxyl groups and a molecular weight of 250 to 1,500, which have a surface tension of 6 to 14 mN/m with respect to i-pentane and/or n-pentane as blowing agent,2. i-pentane and/or n-pentane as blowing agent,3. water and4. optionally auxiliary agents and additiveswithB) a polyisocyanate with an NCO-content of 20 to 48 wt. % which has a surface tension of 4.0 to 8 mN/m with respect to i-pentane or n-pentane as blowing agentis described.

Abstract: This invention provides a process for producing rigid polyurethane foams by reacting A) a polyol component with B) a polyisocyanate component in the presence of C) water, D) at least one catalyst, and, optionally, E) at least one blowing agent. This process specifically requires A) a polyol component which comprises: 1) a polyol containing at least two isocyanate-reactive hydrogen atoms and comprising: a) a mixture of i) an addition product having a OH number of at least 500 of diamines or polyamines containing primary and/or secondary amino groups with alkylene oxides, and ii) castor oil, and/or b) one or more reaction products obtained by reacting i) an addition product having a OH number of at least 500 of diamines or polyamines containing primary and/or secondary amino groups with alkylene oxides, and ii) castor oil; and 2) at least one compound containing at least two isocyanate-reactive hydrogen atoms.

Abstract: A process is described for the preparation of stable, agglomerate-free, low-viscosity graft copolymer dispersions by the free-radical polymerization of olefinic monomers, such as styrene and/or acrylonitrile, with polyol compounds in the presence of a hydroxyl compound modified with castor oil. The use of these graft copolymer dispersions in the manufacture of polyurethane plastics, particularly flexible foams, by the isocyanate polyaddition process is also described.

Abstract: A continuous process for the preparation of highly stable, finely divided, low viscosity polymer polyols of small average particle size wherein in the first step an intermediate is prepared by reacting (1) a mixture of at least two ethylenically unsaturated monomers, preferably styrene and acrylonitrile, in a mixture comprising (2) a base polyol and (3) a macromer in the presence of (4) a free radical initiator, (5) a solvent having moderate chain transfer activity, and, optionally, (6) a reaction moderator at a temperature of at least 100.degree. C., such that the intermediate contains at least about 12% by weight of macromer, based on the weight of the base polyol and macromer, and a solids content of at least about 15% by weight and less than about 30% by weight, based on the weight of the base polyol, macromer and ethylenically unsaturated monomers.

Abstract: Stable, agglomerate-free, low-viscosity graft copolymer dispersions are prepared by the radical polymerization of 25 to 65% by weight of ethylenically unsaturated monomers in the presence of a base polyol, a macromer, a low-molecular weight regulator and, optionally, an organic solvent. The dispersions of this process are suitable as a polyol component for the production of polyurethane plastics by the isocyanate addition process.

Abstract: A process for the production of stable, agglomerate-free, low viscosity graft copolymer dispersions through radical polymerization of ethylenically unsaturated monomers in the presence of a base polyol, a macromer, an enol ether of a specific formula, and optionally, an organic solvent. These enol ethers correspond to the general formula:A=CH--O--Rwherein:A represents a di-valent residue of the formula ##STR1## R represents an aliphatic hydrocarbon radical having 1 to 18 carbon atoms, a cycloaliphatic hydrocarbon radical having 5 to 10 carbon atoms, or a substituted or unsubstituted benzyl radical;andR' represents a hydrogen atom or an aliphatic hydrocarbon radical having 1 to 8 carbon atoms.