摘要:
The present invention relates to a process for the preparation of plastics containing thermoplastic polyurethanes and optionally other components comprising (a) melting and homogenizing a thermoplastic polyurethane in an extruder, and (b) adding an isocyanate to said extruder containing the melted and homogenized thermoplastic polyurethane.
摘要:
The present invention relates to a process for the preparation of plastics containing thermoplastic polyurethanes and optionally other components comprising (a) melting and homogenizing a thermoplastic polyurethane in an extruder, and (b) adding an isocyanate to said extruder containing the melted and homogenized thermoplastic polyurethane.
摘要:
The present invention relates to the continuous production of polyurethane and polyurethane urea elastomers by reaction of polyisocyanates with isocyanate-reactive compounds in a mixing nozzle.
摘要:
The invention is directed to a process for the production of polyurethanes suitable for thermoplastic processing comprising mixingI. at least 75% by weight of preformed thermoplastic polyurethane elastomers, or of a blend of(A) substantially bifunctional, compounds(B) substantially bifunctional chain-extending agents(C) organic diisocyanates and optionally(D) lubricants or other known additivessaid blend characterized in that it contains no peroxides and polymerization initiators which decompose into radicals under the effect of actinic light and further in that the molar ratio of the sum of said (A) and said (B) to said (C) is between 0.9 to 1.1, withII. (E) from 4 to 24% by weight of a crosslinking agent andIII. (F) from 0.01 to 3% by weight of a polymerization inhibitor and/or an antioxidant,by adding said II and said III to said I at a temperature below 230.degree. C., and the cooling the mixture to below 130.degree. C. in less than 5 minutes in a continuous extruder and optionally granulating the resulting polyurethane.