Abstract: The present invention relates to high-quality polyurethane and polyurethane urea elastomers which exhibit unique combinations of processing characteristics, oxidation resistance, mechanical and mechanical/dynamic properties in particularly demanding applications. These polyurethane elastomers and polyurethane urea elastomers are based on novel polycarbonate polyols.

Abstract: Polyurethane prepolymers are described which are prepared from 2,4?-diiso-cyanate diphenylmethane (2,4?-MDI), a polyol component and an aliphatic diisocyanate. These prepolymers can be cured with aliphatic, cycloaliphatic and/or aromatic amines to form a cured urethane elastomer. In comparison to cured urethane elastomers based on monomeric 2,4?-MDI, these prepolymers provide elastomers with extended pour life, i.e. they exhibit a slower rate of viscosity buildup after curative and prepolymer are mixed which results in a reduced propensity to crack during the curing process and gives the opportunity to cast larger parts. In comparison to polyurea/urethanes prepared from cured TDI-prepolymers and which optionally include H12-MDI, the prepolymers of the invention have better health and safety aspects.

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 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 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 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.

Abstract: Polyurethane prepolymers are described which are prepared from 2,4?-diiso-cyanate diphenylmethane (2,4?-MDI), a polyol component and an aliphatic diisocyanate. These prepolymers can be cured with aliphatic, cycloaliphatic and/or aromatic amines to form a cured urethane elastomer. In comparison to cured urethane elastomers based on monomeric 2,4?-MDI, these prepolymers provide elastomers with extended pour life, i.e. they exhibit a slower rate of viscosity buildup after curative and prepolymer are mixed which results in a reduced propensity to crack during the curing process and gives the opportunity to cast larger parts. In comparison to polyurea/urethanes prepared from cured TDI-prepolymers and which optionally include H12-MDI, the prepolymers of the invention have better health and safety aspects.

Abstract: The present invention relates to high-quality polyurethane and polyurethane urea elastomers which exhibit unique combinations of processing characteristics, oxidation resistance, mechanical and mechanical/dynamic properties in particularly demanding applications. These polyurethane elastomers and polyurethane urea elastomers are based on novel polycarbonate polyols.

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: Thermoplastic polyurethanes (TPU) based on NDI are prepared by reacting specific, storage-stable NDI-based NCO prepolymers with chain extenders and granulating the largely reacted and cooled reaction melt. The TPU granules can then be processed to form shaped articles.

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 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.

Abstract: Polyurethane (PUR) cast elastomers are produced from NCO-functional prepolymers based on 2,4?-MDI satisfying specific compositional requirements and amine-based chain extenders and/or crosslinking agents.

Abstract: Polyurethanes are produced using 2,2?-thiodiethanol as the chain lengthener. These polyurethanes are useful for the production of cast elastomers.

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 present invention relates to poly(urethane carbonate) polyols, to a process for their preparation and to their use.

Abstract: The present invention relates to a process for the preparation of clear, storage-stable isocyanate-terminated prepolymers. These isocyanate-terminated prepolymers are based on hexanediolether carbonate. This invention also relates to the preparation of polyurethanes from these isocyanate-terminated prepolymers.

Abstract: The present invention relates to a method for preparing oligomeric aliphatic diols, polycarbonatediols based thereon and NCO-terminated prepolymers obtainable therefrom. The inventive compounds may find use in the preparation of polyurethanes.

Abstract: The polyester polyols according to the invention with an average equivalent weight in the range from 200 to 4,000, which were prepared by reacting &agr;,&ohgr;-dicarboxylic acids with butane 1,4-diol, hexane 1,6-diol, propane 1,3-diol or pentane 1,5-diol and with polyols having 3 to 6 hydroxyl groups, are used for the preparation of PUR pourable elastomers with improved resistance to hydrolysis.

Abstract: The present invention relates to a method for preparing oligomeric aliphatic diols, polycarbonatediols based thereon and NCO-terminated prepolymers obtainable therefrom. The inventive compounds may find use in the preparation of polyurethanes.