| 摘要 |
At least one isocyanate-reactive monomer is reacted with an excess of molten monomeric diisocynate to produce at least one reaction product and a maximum of 0.5 wt % of free isocyanate groups. The reaction product is then mixed with at least 20 wt. %, based on the total weight of reaction product, of at least one isocyanate-terminated prepolymer which is essentially free of diisocyanate monomers and has a viscosity at 20° C. of at least 1.500 mPa.s, the isocyanate-terminated prepolymer having a content of free NCO groups of up to 25 wt % and containing a maximum of 0.1 wt. % of diisocyanate monomer(s) based on the weight of the isocyanate-terminated prepolymer. A polyurethane composition containing less than 0.1 wt. % of monomeric diisocyanate, based on the total weight of the resulting polyurethane composition, is produced.
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