Thermoplastic polyurethanes having selfextinguishing properties, a process for their preparation and use.

摘要

A thermoplastically processable polyurethane elastomer (TPU), comprises a reaction product of a prepolymer containing isocyanate groups, which comprises the reaction product of at least one organic diisocyanate and at least one polyol, with at least one low molecular weight polyol or polyamine and at least one organic phosphorus-containing compound, and optionally in the presence of catalyst(s), flameproofing agent(s) and/or additive(s). A thermoplastically processable polyurethane elastomer (TPU) having a tensile strength of greater than 35 MPa, with shrinkages of less than 3% and with self-extinguishing properties, comprises a reaction product of a prepolymer containing isocyanate (NCO) groups, which comprises the reaction product of at least one organic diisocyanate and at least one polyol having in average at least 1.8 and not more than3 Zerewitinoff-active hydrogen atoms and a number-average molecular weight Mn of 450-10000, with at least one low molecular weight polyol or polyamine having on average at least 1.8 and not more than3 Zerewitinoff-active hydrogen atoms and a number-average molecular weight Mn of 60-400 as a chain lengthener and 1-15 wt.%, based on the total weight of the TPU, of at least one organic phosphorus-containing compound consisting of phosphonates or phosphine oxides having on average at least 1.5 and not more than3 Zerewitinoff-active hydrogen atoms and a number-average molecular weight Mn of 60-10000, corresponding to formulae (I) or (II), and optionally in the presence of catalyst(s), 0-70 wt.%, based on the total weight of the TPU, of flameproofing agent(s) containing no Zerewitinoff-active hydrogen atoms and having a number-average molecular weight Mn of 60-10000, and/or 0-20 wt.%, based on the total weight of TPU, of further auxiliary substances additive(s). The isocyanate index is 85-120. (Structures (I-II), pages 8-9) R1 and R2 = 1-24C alkylene radical, optionally substituted 6-20C arylene radical, optionally substituted 6-30C aralkylene radical, or optionally substituted 6-30C alkarylene radical; R3 = H, 1-24C alkyl radical, optionally substituted 6-20C aryl radical, optionally substituted 6-30C aralkyl radical, or optionally substituted 6-30C alkaryl radical; x and y = 1-50; R1' = R3; R2' and R3' = R1. An Independent claim is also included for a process for the preparation of thermoplastically processable polyurethane elastomers, comprising preparing a prepolymer containing NCO groups by reacting at least one organic diisocyanate with at least one polyol; and reacting the prepolymer with at least one low molecular weight polyol or polyamine, and at least one organic phosphorus-containing compound, the steps being optionally carried out in the presence of catalyst(s) and optionally with the addition of at least one further flameproofing agent and/or further auxiliary substances and additives.