Abstract: Polyesterols having reduced reactivity are prepared by catalytic polycondensation of dicarboxylic acids/dicarboxylic acid derivatives and H-functional substances using tin catalysts by a process wherein the polyesterols are brought into contact with oxygen after the end of the esterification reaction. The polyesterols themselves obtained by this process are used for the preparation of PU.

Abstract: The invention relates to isocyanate adducts which can be prepared by reacting at least one polyisocyanate with compounds having at least two hydrogen atoms which are reactive toward isocyanate groups and have a crystalline content of less than 10 J/g determined by differential scanning calorimetry in accordance with DIN 51 004 at 20 K/min from room temperature to 250° C. using a nitrogen flow of 3 l/h as carrier gas and an aromatics content reported as carbon atoms in aromatic rings of less than 31% by weight, based on the total weight of the isocyanate adducts.

Abstract: The invention relates to high-functionality polyether polyols of the general formula where each R?1 is an unsubstituted or substituted aliphatic or aromatic radical and each R?2 is an unsubstituted or substituted aliphatic or aromatic radical, H, OH, polyalkyl ether chain or halogen, each X is a polyalkyl ether chain or H, where at least one X is a polyalkyl ether chain, and m is an integer from 0 to 20, where Xm is H when m is 0, and n is an integer from 4 to 12, to processes for preparing such high-functionality polyether polyols and also to the use thereof for preparing polyurethanes and nonionic surfactants.

Abstract: Polyesterols having reduced reactivity are prepared by catalytic polycondensation of dicarboxylic acids/dicarboxylic acid derivatives and H-functional substances using tin catalysts by a process wherein the polyesterols are brought into contact with oxygen after the end of the esterification reaction. The polyesterols themselves obtained by this process are used for the preparation of PU.

Abstract: The invention relates to a foam comprising at least 70% by weight of carbon and having a mean cell size above 20 ?m, a porosity based on this cell size of from 35% to 99.5% and an open cell content above 90%, an internal surface above 50 m2/g, having cell struts whose cross section is a triangle having concave sides and having pores in the cell framework material having dimensions of from 0.2 nm to 50 nm and a volume of from 0.01 cm3/g to 0.8 cm3/g, and also to its use. It further relates to a process for producing a foam comprising at least 70% by weight of carbon by pyrolysis of polymer foams which comprise at least 30% by mass of a polymer material having a nitrogen content of more than 6% by mass and having a porosity of from 35 to 99.5% and an open cell content above 1%, have inorganics incorporated into the polymer foam and/or applied to the surface and/or are treated during and/or after the pyrolysis with water vapor and/or carbon dioxide and/or oxygen at above 400° C.

Abstract: The invention relates to isocyanate adducts which can be prepared by reacting at least one polyisocyanate with compounds having at least two hydrogen atoms which are reactive toward isocyanate groups and have a crystalline content of less than 10 J/g determined by differential scanning calorimetry in accordance with DIN 51 004 at 20 K/min from room temperature to 250° C. using a nitrogen flow of 3 l/h as carrier gas and an aromatics content reported as carbon atoms in aromatic rings of less than 31% by weight, based on the total weight of the isocyanate adducts.

Abstract: Prepolymers which contain isocyanate groups, have an NCO content of at least 30.0% by weight and can be prepared by reacting an isocyanate mixture consisting predominantly of diphenylmethane diisocyanates and polyphenylpolymethylene polyisocyanates and having a proportion of two-ring isomers of not more than 74% by weight with at least 4-functional polyols or a mixture of polyols having a mean functionality of at least 4, where the polyols or polyol mixtures have a hydroxyl number of from 200 to 1650 mg KOH/g and a number average molecular weight of less than 1100 g/mol.

Abstract: Thermally stable rigid foams based on isocyanate can be produced by reacting a) polyisocyanates with b) compounds containing at least two hydrogen atoms which can react with isocyanate groups, c) water, in the presence of d) physically acting blowing agents, in the presence or absence of e) catalysts and auxiliaries and/or additives, wherein the component b) comprises bi) at least one polyether alcohol having a functionality of at least 1.5 and a hydroxyl number of from 10 to 100 mg KOH/g in an amount of from 0.2 to 80% by mass, based on b), and bii)at least one polyester alcohol in an amount of from 5 to 90% by mass, based on b), the water c) is present in an amount of at most 2% by mass, based on the sum of the components b) to e), and the component d) used comprises hydrocarbons and/or fluorine-containing hydrocarbons in an amount of from 5 to 30% by mass, based on the sum of the components b) to e).

Abstract: Storage-stable, blowing agent-containing halogen-free emulsions for producing rigid foams based on isocyanate comprise a) compounds containing hydrogen atoms which are reactive toward isocyanate groups, b) water, c) physically acting, halogen-free blowing agents and, if desired, d) auxiliaries and/or additives which are customary in polyurethane chemistry, wherein the component a) comprises polyether alcohols having a functionality of greater than 1.5 and a hydroxyl number of from 10 to 100 mg KOH/g in an amount of from 0.2% by mass to 80% by mass, based on the mass of the component a), and the halogen-free, physically acting blowing agents c) used are hydrocarbons having from 3 to 10 carbon atoms.

Abstract: Diisocyanates of the formula (I) where R1 is a C1-C10-hydrocarbon radical and R3 is a C1-Cl2-hydrocarbon group and n is an integer from 1 to 10, are described.

Abstract: A microcellular PU elastomer having improved dynamic-mechanical properties and based on an isocyanate component consisting essentially of 4,4'-MDI and also further customary constituents has, after heating at from 100 to 120.degree. C. for from 8 to 24 hours, a melting range of from 130.degree. C. as the minimum lower limit to 230.degree. C. as a minimum upper limit, measured by differential scanning calorimetry (DSC) at a heating rate of 20.degree. C./min, and a urea content of from 14 to 18% by weight.A process is also provided for preparing such a microcellular PU elastomer having improved dynamic mechanical properties. The microcellular PU elastomers can be used for producing damping elements.

Abstract: Rigid polyurethane foams having a low thermal conductivity are produced by reactinga) organic and/or modified organic polyisocyanates withb) at least one compound containing at least 2 reactive hydrogen atoms in the presence ofc) blowing agents,d) catalysts and, if desired,e) auxiliaries and/or additives,wherein graphite is added to the component a) and/or b).

Abstract: A process for producing rigid polyurethane foams with reduced density by reactinga) organic and/or modified organic polyisocyanates withb) at least one higher-molecular-weight compound having at least two reactive hydrogen atoms and, if desired,c) low-molecular-weight chain extenders and/or crosslinkers in the presence ofd) blowing agents,e) catalysts and, if desired,f) other auxiliaries and/or additives,is described, which comprises using, as blowing agent (d), a mixture of cyclopentane with at least one compound which is homogeneously miscible with cyclopentane selected from the class consisting of the alkanes and/or alkenes having 3 or 4 carbon atoms in the molecule and with the carbon dioxide produced from water and isocyanate, and using, as higher-molecular-weight compound (b) having at least two reactive hydrogen atoms, polyethers which contain aromatics and nitrogen.The use of the rigid foams produced in this way as insulating material is also described.

Abstract: A microcellular PU elastomer having improved dynamic mechanical properties and based on an isocyanate component consisting essentially of 4,4'-MDI and further customary constituents has a physicochemical structure which, in the gel permeation chromatograph (GPC) of a solution of the microcellular polyurethane elastomer prepared at 90.degree. C. in N,N-dimethylformamide containing 1 percent of di-n-butylamine measured against polymethyl methacrylate (PMMA) as standard, displays a signal occurring in addition to low molecular weight main signal and comprising one or more peaks at an (apparent) molar mass of greater than 250,000 g/mol which becomes smaller or disappears on addition of lithium chloride to this solution, and a urea content of from 14 to 18% by weight.A process is also provided for preparing such a microcellular PU elastomer having improved dynamic mechanical properties. The microcellular PU elastomers can be used for producing damping elements.

Abstract: The present invention relates to thermal insulation gas mixtures comprising cyclopentane and argon for filling cavities.

Abstract: Blowing agent-containing emulsions comprisea) compounds containing hydrogen atoms which are reactive toward isocyanates,b) blowing agents,c) catalysts, auxiliaries and/or additives which are customary in polyurethane chemistry, wherein the blowing agents b) are present as an emulsion in the components a) and c), and polyester alcohols having the following structure are used as emulsification aids: ##STR1## where m=0-15n=0-1o=0-15p=0-1q=0-15r=0-1s=0-15t=0-1u=0-10v=0-15x=1-5y=1-4 or mixtures of 1-3 where r+n.noteq.0z=0-3z.sub.i =0.1-3R.sub.1 is an aliphatic structure without OH groups, based on the structure of polyhydric alcohols, preferably ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propylene glycol and dipropylene glycol, 1,4-butanediol, 1,6-hexanediol, neopentyl glycol, 1,3-butanediol, trimethylolpropane, trimethylol ethane, glycerol, pentaerythritol, where these substances can also be used as any mixture with one another in the esterification and R.sub.

Abstract: In a process for producing rigid polyurethane foams having improved heat distortion resistance and reduced thermal conductivity by reactinga) polyisocyanates withb) compounds containing hydrogen atoms reactive toward isocyanates, in the presence ofc) water, and, if desired,d) physically acting blowing agents ande) catalysts and known auxiliaries and/or additives, the compounds b) containing hydrogen atoms reactive toward isocyanates are a polyol mixture comprisingb1) a polyol which can be prepared by addition of ethylene oxide and/or propylene oxide onto a hexitol or a hexitol mixture, with the total hexitol content of the polyol mixture being from 15 to 30% by weight, based on the polyol mixture, andb2) a polyol which can be prepared by addition of ethylene oxide and/or propylene oxide onto one or more aromatic amines, with the total amine content of the polyol mixture being from 1 to 10% by weight, based on the polyol mixture, and the amount of the polyol mixture in the component b) is from 60 to 100 parts

Abstract: In a process for producing open-celled rigid foams by reactinga) polyisocyanates withb) compounds containing hydrogen atoms which are reactive toward isocyanates, in the presence ofc) water,d) if desired, organic compounds acting as physical blowing agents,e) catalysts, auxiliaries and/or additives,the compounds containing reactive hydrogen atoms used are substances having the structure I: ##STR1## where m is 0-15n is 0-1o is 0-15p is 0-1q is 0-15r is 0-1s is 0-15t is 0-1u is 0-10v is 0-15x is 1-5y is 1-4 or mixtures of 1-3 where r+n.noteq.0z is 0-3z.sub.i is 0.1-3R.sub.1 is an aliphatic structure without OH groups based on the structure of polyhydric alcohols, preferably ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propylene glycol and dipropylene glycol, 1,4-butanediol, 1,6-hexanediol, neopentyl glycol, 1,3-butanediol, trimethylolpropane, trimethylolethane, glycerol, pentaerythritol, where these substances can also be used in the esterification as any mixture among one another and R.sub.

Abstract: In a process for producing rigid foams based on isocyanate, the blowing agent used is a mixture of at least one low-boiling hydrocarbon having from 3 to 7 carbon atoms, low molecular weight monohydric alcohols containing primary or secondary hydroxyl groups and having from 1 to 4 carbon atoms, and, if desired, the carbon dioxide formed from water and isocyanate. The rigid foams can be used as insulation material.

Abstract: In a process for producing rigid foams based on isocyanate, the blowing agent used is a mixture of at least one low-boiling hydrocarbon having from 3 to 7 carbon atoms, low molecular weight monohydric alcohols containing primary or secondary hydroxyl groups and having from 1 to 4 carbon atoms, and, if desired, the carbon dioxide formed from water and isocyanate. The rigid foams can be used as insulation material.