摘要:
The present invention relates to lightfast and hydrolytically resistant molded polyurethane parts with excellent strength properties and a high temperature resistance and colorfastness to light at elevated temperatures for sophisticated applications in the sector of automobile interiors, which products are produced from a reaction mixture of aliphatic and/or cycloaliphatic compositions by using a cost-effective reaction injection molding method (RIM) or a casting method that requires only a short mold residence time. To this end, A) a composition composed of A1) an OH-terminated trifunctional prepolymer, A2) a polyol or a polyol combination, A3) at last one di- and/or trifunctional chain-lengthening agent and/or crosslinking agent with amine and/or hydroxyl groups, and A4) a catalyst system, and optionally A5) a stabilizer system, and optionally A6) at least one additive, and B) an isocyanate composition, are reacted.
摘要:
A method for production of a reactive polyurethane emulsion for use in impregnating and coating a textile fabric includes reacting polyols alone or in combination with at least one of diols and triols with a substoichiometric amount of diisocyanates so as to form medium-viscosity, OH-terminated prepolymers. The prepolymers are mixed with an external emulsifier. At least one of a diisocyanate, a triisocyanate and a polyisocyanate are added so as to bring about a crosslinking of the prepolymers.
摘要:
A method for manufacturing a synthethic leather includes the steps of obtaining a polyurethane prepolymer from isocyantates and linear hydroxyl-terminated polyols having molecular weights of 500 to 5,000 g/mol, wherien the isocyanates include at least one of aliphatic, cyclophatic, and non-aromatic heterocyclic di- and or tri-isocyanates. A first aqueaous dispersion of the polyurethane prepolymer is provided and mixed with a second aqueous dispersion or solution of a catalyst and at least one cross-linking constituent so as to create a mixture. The method further includes impregnating a textile fabric with the mixture and drying and reacting the prepolymers to completion at a temperature from 80 to 180° C. In addition, a synthetic letter manufactured according to the method.