abstract |
The invention relates to a method for producing a molded body (FK), comprising producing a thermoplastic polyurethane, producing a molded body (FK*) from the thermoplastic polyurethane, heating the molded body (FK*) to a temperature below the temperature at which there is permanent deformability of the molded body (FK*) and above the switching temperature of the thermoplastic polyurethane, elongating the heated molded body (FK*) and thus obtaining a molded body (FK), and cooling the molded body (FK) to a temperature below the switching temperature of the thermoplastic polyurethane. The invention further relates to molded bodies that are or can be obtained in accordance with such a method. The thermoplastic polyurethane comprises a polyisocyanate composition, a chain extender, and a polyol composition having at least one bisphenol derivative selected from the group comprising bisphenol A derivatives having a molecular weight Mw of > 315 g/mol and bisphenol S derivatives having a molecular weight Mw of > 315 g/mol, wherein at least one of the OH groups of the bisphenol derivative is alkoxylated. The invention further relates to the use of a thermoplastic polyurethane to produce a molded body having a shape memory effect in a temperature from 20 °C to 120 °C. |