Isocyanate-Containing Thermoplastic Polyurethane

Abstract

Thermoplastic polyurethane (i) comprising from 20% by weight to 70% by weight of isocyanate dissolved in the thermoplastic polyurethane, based on the total weight of the thermoplastic polyurethane (i) comprising the isocyanates.

1 - 21 . (canceled) 
     
     
         22 . A thermoplastic polyurethane (i) comprising from 20% by weight to 70% by weight of isocyanate dissolved in the thermoplastic polyurethane, based on the total weight of the thermoplastic polyurethane (i) comprising the isocyanates. 
     
     
         23 . The thermoplastic polyurethane (i) of  claim 22 , wherein the NCO content of the thermoplastic polyurethane (i) comprising the isocyanate is greater than 5%. 
     
     
         24 . The thermoplastic polyurethane (i) of  claim 22 , wherein diphenylmethane 2,2′-, 2,4′- and/or 4,4′-diisocyanate (MDI), a carbodiimide-modified diphenylmethane 2,2′-, 2,4′- and/or 4,4′-diisocyanate (MDI), a prepolymer based on diphenylmethane 2,2′-, 2,4′- and/or 4,4′-diisocyanate (MDI), isocyanates comprising biuret and/or isocyanurate groups are present as isocyanate in the thermoplastic polyurethane (i). 
     
     
         25 . The thermoplastic polyurethane (i) of  claim 22 , wherein carbodiimide-modified diphenylmethane 4,4′-diisocyanate (MDI), prepolymer based on ethylene oxide/propylene oxide and/or trimerized hexamethylene diisocyanate are present as isocyanate in the thermoplastic polyurethane (i). 
     
     
         26 . The thermoplastic polyurethane (i) of  claim 22 , wherein the thermoplastic polyurethane in which the isocyanate is dissolved has a Shore hardness of from 80 A to 60 D before incorporation of the isocyanate. 
     
     
         27 . The thermoplastic polyurethane (i) of  claim 22 , wherein the thermoplastic polyurethane (i) is in the form of pellets. 
     
     
         28 . A process for producing the thermoplastic polyurethane (i) comprising isocyanate of  claim 22 , comprising melting the thermoplastic polyurethane and subsequently incorporating the isocyanate into said melt. 
     
     
         29 . The process of  claim 28 , wherein thermoplastic polyurethane is melted at temperatures of from 170 to 240° C. and the isocyanate at a temperature in the range from 20 to 80° C. is subsequently mixed into this melt so that the resulting mixture has a temperature in the range of from 120 to 160° C. 
     
     
         30 . The process of  claim 28 , wherein the isocyanate is incorporated into the thermoplastic polyurethane by means of an extruder. 
     
     
         31 . The process of  claim 30 , wherein the isocyanate is incorporated into the thermoplastic polyurethane by means of a twin-screw extruder. 
     
     
         32 . The process of  claim 30 , wherein the product obtained from the extruder, i.e., the thermoplastic polyurethane (i) comprising isocyanate, is cooled in a water bath immediately after leaving the die of the extruder and the strand obtained is subsequently pelletized. 
     
     
         33 . The process of  claim 30 , wherein the product obtainable from the extruder, i.e., the TPU melt (i) comprising the isocyanate, is extruded through a multihole dye directly from the extruder into a water bath and is subsequently cut up by means of a rotating knife. 
     
     
         34 . A process for producing polyurethanes comprising reacting (a) isocyanates with (b) compounds which are reactive toward isocyanates, wherein the production is carried out in the presence of the thermoplastic polyurethanes (i) of  claim 22 . 
     
     
         35 . A process for reacting thermoplastic polyurethanes with isocyanate, wherein the thermoplastic polyurethane (i) comprising isocyanates of  claim 22  is used as isocyanate. 
     
     
         36 . The process of  claim 35 , wherein from 1 to 70 parts by weight of thermoplastic polyurethane (i) comprising isocyanates according to any of claims  1  to 6 are used per 100 parts by weight of thermoplastic polyurethane. 
     
     
         37 . The process of  claim 35 , wherein the thermoplastic polyurethane (i) is introduced into an extruder and melted together with the thermoplastic polyurethane. 
     
     
         38 . A process for injection molding thermoplastic polyurethane, wherein thermoplastic polyurethane is injection molded together with the thermoplastic polyurethane (i) comprising isocyanates of  claim 22 . 
     
     
         39 . The process for injection molding the thermoplastic polyurethane of  claim 38 , wherein thermoplastic polyurethane is injection molded by two-component injection molding together with a thermoplastic polyurethane (i) comprising from 20% by weight to 70% by weight of isocyanate dissolved in the thermoplastic polyurethane, based on the total weight of the thermoplastic polyurethane (i) comprising the isocyanates. 
     
     
         40 . An injection-molded article obtained by the process of  claim 38 . 
     
     
         41 . An extruded article obtained by the process of  claim 35 . 
     
     
         42 . A film obtained by the process of  claim 35