| 摘要 |
The invention relates to a method for producing a thermoplastic polyurethane elastomer based on polyether carbonate polyols. The method comprises a first step, in which at least A) an organic diisocyanate and B) a polyol having a number-average molecular weight Mn>=500 and <=5000 g/mol are reacted to form an isocyanate-terminated prepolymer. In a second step, the prepolymer is reacted with C) one or more chain extenders having a molecular weight>=60 and <=490 g/mol and optionally D) a monofunctional chain stopper or E) an organic diisocyanate, wherein optionally at least F) one catalyst is used in the first and/or second step.; The molar ratio of the sum of the isocyanate groups from A) and, if applicable, E) to the sum of the groups reactive to isocyanate in B), C), and, if applicable, D) is >=0.9:1 and <=12:1, and component B) contains at least one polyether carbonate polyol, which can be obtained by adding carbon dioxide and alkylene oxides to H-functional starter substances. The invention further relates to a thermoplastic polyurethane elastomer produced in accordance with the method according to the invention, the use of said thermoplastic polyurethane elastomer to produce extruded or injection molded items, and the items produced by extrusion or injection molding. |
