Abstract: The present invention relates to a process for producing polyether polyols having primary hydroxyl end groups, comprising the steps of reacting a starter compound containing active hydrogen atoms with an epoxide under double metal cyanide catalysis, reacting the resulting product with a cyclic carboxylic anhydride and reacting this resulting product with ethylene oxide in the presence of a catalyst containing at least one nitrogen atom per molecule, excluding non-cyclic, identically substituted tertiary amines. The invention further relates to polyether polyols obtainable by this process, compositions containing said polyols and polyurethane polymers based on said polyols.

Abstract: The present invention relates to a polyurea system, the use of such a polyurea system for sealing, linking, gluing, or covering of cellular tissue, and a dosing system having two chambers for a polyurea system such as this. The polyurea system comprises as components: A) an isocyanate-functioning prepolymer, which can be derived by reacting aliphatic isocyanates with polyoles, and B) an amino-functioning ester of aspartic acid. According to the invention, water and/or tertiary amine is added to the system, in order to increase the reacting speed of the prepolymer with the amino-functioning ester of aspartic acid while decreasing the setting time at the same time.

Abstract: The present invention relates to the production and use of polyester polyols produced from at least one aromatic dicarboxylic acid or an alkyl ester of an aromatic dicarboxylic acid or the anhydride of an aromatic dicarboxylic acid and at least one ?,?-diol, wherein the formation of 1,4-dioxane from diethylene glycol is largely suppressed by means of specific reaction management.

Abstract: The present invention relates to a method for producing a polyester polyol having a concentration of ether groups in the range from 9.0 mol/kg of polyester polyol to 22 mol/kg polyester polyol, characterized in that (i) in a first step (A) isophthalic acid, optionally in the form of a C1-C4 alkyl ester, and/or terephthalic acid, optionally in the form of a C1-C4 alkyl ester, is reacted with (B) oligoethylene glycol of the formula H—(OCH2CH2)n—OH having a numerical average number of oxyethylene groups n in the range from 3.0 to 9.0, in the presence of at least one catalyst selected from the group made up of tin(II) salts, bismuth(II) salts, and titanium tetraalkoxylates, at a temperature in the range from 160° C. to 240° C.

Abstract: The invention relates to a process for the preparation of a polyurethane polymer, comprising the step of reaction of A) polyester polyols with secondary hydroxyl end groups, which are obtainable from the reaction of a polyester comprising carboxyl end groups with an epoxide of the general formula (1): wherein R1 represents an alkyl radical or an aryl radical and wherein the polyester comprising carboxyl end groups has an acid number of from ?25 mg of KOH/g to ?400 mg of KOH/g and a hydroxyl number of ?5 mg of KOH/g, with B) polyisocyanates which are chosen from the group comprising toluoylene-diisocyanate, diphenylmethane-diisocyanate, polymeric diphenylmethane-diisocyanate, xylylene-diisocyanate, naphthylene-diisocyanate, hexamethylene-diisocyanate, diisocyanatodicyclohexylmethane and/or isophorone-diisocyanate. The invention furthermore relates to polyurethane polymers prepared by such a process.

Abstract: The invention relates to a process for producing polyester polyols with secondary hydroxyl end groups, including the step of the reaction of a polyester including carboxyl end groups with an epoxide of the general formula (1): wherein R1 stands for an alkyl residue or an aryl residue and the reaction is carried out in the presence of a catalyst that includes at least one nitrogen atom per molecule. The process is distinguished in that the polyester including carboxyl end groups exhibits an acid value from ?25 mg KOH/g to ?400 mg KOH/g and a hydroxyl value from ?5 mg KOH/g and in that the polyester including carboxyl end groups is produced by ?1.03 mol to ?1.90 mol carboxyl groups or carboxyl-group equivalents of an acid component being employed per mol hydroxyl groups of an alcohol. The polyester polyols obtained, including secondary hydroxyl end groups, can be used for the purpose of producing polyurethane polymers.

Abstract: Polyester polyols are produced by reacting terephthalic acid with a glycol corresponding to the formula H—(OCH2CH2)n—OH and an aliphatic dicarboxylic acid.

Abstract: Stable NCO prepolymers are produced from polyisocyanates having a melting point greater than 70° C., preferably, naphthalene diisocyanate, having advantageous physical properties. An important feature of the process of the present invention is the rapid cooling of the prepolymer. The process of the present invention may be carried out on a continuous or batch basis. The prepolymers of the present invention are particularly suitable for the production of cast polyurethane elastomers.

Abstract: The invention relates to carbon nanotubes comprising hydroxy groups, wherein the surface thereof comprises hydroxy alkyl ester groups covalently bound thereon, chosen from the group according to the general formula (1) and/or the general formula (2), wherein (CNT) stands for the surface of the carbon nanotube and R1 and R2 are independently from each other hydrocarbon, an alkyl radical or an aryl radical. The invention further relates to a method for the production thereof by means of reaction of carbon acid groups of the carbon nanotubes with an epoxy, furthermore a polyurethane polymer, wherein said carbon nanotubes are covalently bound, a method for producing a polymer of said kind and use of the carbon nanotubes for producing polymers.

Abstract: The present invention relates to a thermoplastically processable polyurethane elastomer having a hardness of 50 Shore A to 70 Shore D (ISO 868), which are obtained from reacting components comprising a) one or more linear polyester diols having a functionality from 1.8 to 2.2, wherein the one or more linear polyester diols comprise succinic acid 1,3-propionate and have an average molecular weight from 1,950 to 4,000 g/mol. b) one or more organic diisocyanates, and c) one or more diols having a molecular weight from 60 to 350 g/mol, wherein the components have a molar NCO:OH ratio of from 0.9:1 to 1.1:1.

Abstract: The invention relates to the production and use of polyester polyols, formed from at least one carboxylic acid hydride and ethylene glycol, wherein a specialized reaction control stustantially suppresses the formation of 1,4-dioxane from diethylene glycol.

Abstract: Polyester polyols are produced from at least one carboxylic acid hydride and diethylene glycol by a process in which the formation of 1,4-dioxane is suppressed. These polyester polyols are useful for producing polyurethane (PUR) and polyisocyanurate (PIR) foams and metal composite elements containing these PUR or PIR foams.

Abstract: The present invention provides an electromechanical transducer comprising a dielectric elastomer with contact by a first electrode and a second electrode, said dielectric elastomer comprising a polyurethane polymer comprising the reaction product of A) a polyisocyanate and/or B) a polyisocyanate prepolymer with C) a compound having at least two isocyanate-reactive groups wherein the polyisocyanate prepolymer B) and/or the compound C) having at least two isocyanate-reactive groups comprise polytetramethylene glycol ether units of the formula (I): —[O—CH2-CH2-CH2-CH2-]n??(I) where n?25; and with a minimum value nmin for the value n and a maximum value nmax for the value n in the formula (I) selected such that the difference between nmax and nmin is ?0 to ?4. The present invention further provides a process for producing such an electromechanical transducer, and to an electric and/or electronic device including the inventive electromechanical transducer.

Abstract: The present invention relates to NCO-terminated prepolymers that are stable to sedimentation, to a process for the production of these NCO-terminated prepolymers, and to the production of polyurethanes from these NCO-terminated polymers.

Abstract: The invention is directed to novel poly(ether-ester)polyols, processes for their production from monocarboxylic or polycarboxylic acid esters with one or more bound polyether chain(s). This invention also relates to the production of polyurethane materials in which the isocyanate-reactive component comprises these poly(ether-ester)polyols.

Abstract: The present invention relates to polymer dispersions in polyester polyols, a process for producing them and their use for the production of polyurethanes, in particular microcellular polyurethanes. These polyester polyols have sulfur atoms and are free of olefinically unsaturated groups.

Abstract: The present invention relates to polymer dispersions in polyester polyols, a process for producing them and their use for the production of polyurethanes, in particular microcellular polyurethanes. These polyester polyols have sulfur atoms and are free of olefinically unsaturated groups.

Abstract: The present invention relates to NCO prepolymers having a low content of free monomeric diisocyanate, to a process for the production of these NCO prepolymers, to polyurethanes prepared from these NCO prepolymers and to processes for the production of these polyurethanes.

Abstract: The present invention relates to polymer dispersions in polyester polyols, a process for producing them and their use for the production of polyurethanes, in particular microcellular polyurethanes. These polyester polyols have sulfur atoms and are free of olefinically unsaturated groups.

Abstract: The present invention relates to polyester polyols with low functionality and a process for their production, to prepolymers prepared from these polyester polyols and a process for their production, and to polyurethanes prepared from these polyester polyols and/or from these prepolymers, and to processes for their production. These polyester polyols are produced in a two-step process. In the second step of this two-step process, one or more cyclic ester monomers is reacted with one or more polyester polyols at low temperatures.